It must however be admitted that in these Churches and ecclesial Communities there exist important differences from the Catholic Church, not only of a historical, sociological, psychological and cultural character, but especially in the interpretation of revealed truth. (Vatican Council II. Decree Unitatis redintegratio, no. 19, November 21, 1964)

It is well known, now, to everybody by the evidence of the facts that the plan conceived by the heretical sects, multiform emanations of Protestantism, is to raise the standard of discord and religious rebellion in the peninsula [of Italy], but mostly in this noble city [of Rome] which God Himself, admirably ordaining the events, established as the center of this fecund and sublime unity, the object of which was the prayer addressed by our divine Savior to His heavenly Father (Jn 17:11, 21), which was jealously guarded by the Popes, even unto the price of their life, despite the oppositions of men and the vicissitudes of time. After having destroyed in their respective homeland, by opposite and dissonant systems, the venerable and ancient beliefs that were part of the sacred deposit of revelation; after having spread the icy breath of uncertainty in the souls of their spectators, of division and skepticism […] these sects have thus introduced themselves into the chosen vineyard of the Lord, with the objective to pursue their devastating task. […] Being made aware of this fact, before anything We suffer the need to confess, as We have done so on other occasions, just how exasperating is the condition imposed upon the head of the Catholic Church, forced to observe the free and progressive development of the heresy in this holy city, from which must shine forth on the world the light of truth and of good example, and which should be the respected See of the Vicar of Jesus Christ. As if this didn’t suffice, to corrupt the mind and heart of the people, from a torrent of unwholesome doctrines and depravations that spring forth with impunity on a daily basis, from professor’s chairs, from theaters, from newspapers, there had to be added to all these causes of perversion the sinister labor of heretical men which, fighting amongst themselves, are but of one accord to inveigh against the Supreme Pontifical Magisterium, the Catholic clergy, and the dogmas of our holy religion, of which they know not the meaning and much less appreciate its august beauty. (Leo XIII. Apostolic letter on protestant proselytism in Rome, August 19, 1900)

You are aware indeed, that the goal of this most iniquitous plot […] This is why they try to draw the Italian people over to Protestantism, which in their deceit they repeatedly declare to be only another form of the same true religion of Christ, thereby just as pleasing to God. Meanwhile they know full well that the chief principle of the Protestant tenets, i.e., that the holy scriptures are to be understood by the personal judgment of the individual, will greatly assist their impious cause. (Pius IX. Encyclical Nostis et nobiscum, no. 6, December 8, 1849)

But later even more care was required when the Lutherans and Calvinists dared to oppose the changeless doctrine of the faith with an almost incredible variety of errors. They left no means untried to deceive the faithful with perverse explanations of the sacred books, which were published by their adherents with new interpretations in the vernacular. (Gregory XVI. Encyclical Inter Praecipuas, no. 4, May 8, 1844)

[Condemned error] 18 – Protestantism is nothing else than a different form of the same true Christian religion, in which it is possible to serve God as well as in the Catholic Church. (Denzinger-Hünermann 2918. Pius IX, Syllabus or collection of modern errors, December 8, 1864)

The Church, founded on these principles and mindful of her office, has done nothing with greater zeal and endeavour than she has displayed in guarding the integrity of the faith. Hence she regarded as rebels and expelled from the ranks of her children all who held beliefs on any point of doctrine different from her own. The Arians, the Montanists, the Novatians, the Quartodecimans, the Eutychians, did not certainly reject all Catholic doctrine: they abandoned only a tertian portion of it. Still who does not know that they were declared heretics and banished from the bosom of the Church? […] The need of this divinely instituted means for the preservation of unity, about which we speak is urged by Saint Paul in his epistle to the Ephesians. In this he first admonishes them to preserve with every care concord of minds: ‘Solicitous to keep the unity of the Spirit in the bond of peace’ (Eph 4:3, et seq.). And as souls cannot be perfectly united in charity unless minds agree in faith, he wishes all to hold the same faith: ‘One Lord, one faith,’ (Leo XIII. Encyclical Satis cognitum, no. 17 – 18, June 26, 1896)

Everyone knows that John himself, the Apostle of love, who seems to reveal in his Gospel the secrets of the Sacred Heart of Jesus, and who never ceased to impress on the memories of his followers the new commandment ‘Love one another,’ altogether forbade any intercourse with those who professed a mutilated and corrupt version of Christ’s teaching: ‘If any man come to you and bring not this doctrine, receive him not into the house nor say to him: God speed you’ (2Jn 10). (Pius XI. Encyclical Mortalium animos, no. 9, January 6, 1928)

Ever since the origins of the early Church, due to the necessity that the faith of the elect be proven like gold in the fire, the Apostle, vessel of election, wished to warn the faithful that if someone arise, of those who alter and amend the Gospel of Christ, spreading false doctrines and betraying the depository of the faith, even if it was an angel who evangelized something other than he had, it would be necessary to anathemize him. (Pius IX. Apostolic Letter Ad Apostolicae Sedis, August 22, 1851)

Now, however, one who carefully considers and reflects on the condition in which the diverse and mutually disagreeing religious societies that are separated from the Catholic Church find themselves… should be able very easily to convince himself that no particular one of those societies or even all of them joined together in any way constitute and are that one and catholic Church that Christ the Lord established, constituted, and willed to exist, nor can they in any way be said to be a member or part of the same Church, because they are visibly separated from the Catholic unity. (Denzinger-Hünermann 2998. Pius IX, Apostolic letter Iam vos omnes, September 13, 1864)

Everyone should avoid familiarity or friendship with anyone suspected of belonging to masonry or to affiliated groups. Know them by their fruits and avoid them. Every familiarity should be avoided, not only with those impious libertines who openly promote the character of the sect, but also with those who hide under the mask of universal tolerance, respect for all religions, and the craving to reconcile the maxims of the Gospel with those of the revolution. These men seek to reconcile Christ and Belial, the Church of God and the state without God. (Leo XIII. Encyclical Custodi di quella fede, no. 15, December 8,1892)

It is impossible for the most true God, who is Truth Itself, the best, the wisest Provider, and the Rewarder of good men, to approve all sects who profess false teachings which are often inconsistent with one another and contradictory, and to confer eternal rewards on their members. […] By it we are taught, and by divine faith we hold one Lord, one faith, one baptism […] This is why we profess that there is no salvation outside the Church. (Leo XII. Encyclical Ubi primum, no. 14, May 5, 1824)

The spouse of Christ cannot be adulterous; she is uncorrupted and pure. She knows one home; she guards with chaste modesty the sanctity of one couch. She keeps us for God. She appoints the sons whom she has born for the kingdom. Whoever is separated from the Church and is joined to an adulteress, is separated from the promises of the Church; nor can he who forsakes the Church of Christ attain to the rewards of Christ. He is a stranger; he is profane; he is an enemy. He can no longer have God for his Father, who has not the Church for his mother. If anyone could escape who was outside the ark of Noah, then he also may escape who shall be outside of the Church. The Lord warns, saying, ‘He who is not with me is against me, and he who gathereth not with me scattereth.’ He who breaks the peace and the concord of Christ, does so in opposition to Christ; he who gathereth elsewhere than in the Church, scatters the Church of Christ. (Saint Cyprian of Carthage. On the Unity of the Church, II, 6)

May the principal concern, for everyone, be to strengthen the character of the Catholic people, inspiring noble and holy intentions, at the same time averting lack of care in which, under the facade of innocent assemblies for young people, conferences for young girls, foreign-language courses, fomenting culture, and subsidies to poor families, is concealed a criminal purpose to insinuate in the minds and hearts the reprobate maxims of heresy. May all the faithful be thoroughly imbued with this truth that nothing can be more valued by them than this treasure that is their Faith, for which their forefathers confronted without trepidation, not only miseries and deprivations, but also often violent persecutions and even death. (Leo XIII. Apostolic letter Sur le prosélytisme protestant à Rome – Lettres Apostoliques de S.S. Léon XIII, lib. VI, Bonne Presse, p.142-145. August 19, 1900)

With the admonition of the apostle that ‘there is one God, one faith, one baptism’ may those fear who contrive the notion that the safe harbor of salvation is open to persons of any religion whatever. They should consider the testimony of Christ Himself that ‘those who are not with Christ are against Him’ (Lk 11:23), and that they disperse unhappily who do not gather with Him. Therefore ‘without a doubt, they will perish forever, unless they hold the Catholic faith whole and inviolate’ (Symbol .s. Athanasius). (Gregory XVI. Encyclical Mirari vos, no. 9, August 15, 1832)

As she has done for the canon of Sacred Scripture and for the doctrine of the faith, the Church, by the power of the Spirit who guides her ‘into all truth,’ has gradually recognized this treasure received from Christ and, as the faithful steward of God’s mysteries, has determined its ‘dispensation’ (Jn 16:13). Thus the Church has discerned over the centuries that among liturgical celebrations there are seven that are, in the strict sense of the term, sacraments instituted by the Lord. The sacraments are ‘of the Church’ in the double sense that they are ‘by her’ and ‘for her’. They are ‘by the Church,’ for she is the sacrament of Christ’s action at work in her through the mission of the Holy Spirit. They are ‘of the Church’ in the sense that ‘the sacraments make the Church’ (Saint Augustine, De civ. Dei, 22, 17; cf. Saint Thomas Aquinas, S Th III, 64,2 ad 3) since they manifest and communicate to men, above all in the Eucharist, the mystery of communion with the God who is love, One in three persons. (Catechism of the Catholic Church, no. 1117 – 1118)

Sacred ministers cannot deny the sacraments to those who seek them at appropriate times, are properly disposed, and are not prohibited by law from receiving them. Pastors of souls and other members of the Christian faithful, according to their respective ecclesiastical function, have the duty to take care that those who seek the sacraments are prepared to receive them by proper evangelization and catechetical instruction, attentive to the norms issued by competent authority. Catholic ministers administer the sacraments licitly to Catholic members of the Christian faithful alone, who likewise receive them licitly from Catholic ministers alone. (Code of Canon Law, Can 843 – 844)

The purpose of the sacraments is to sanctify men, to build up the body of Christ, and, finally, to give worship to God. […] It is therefore of the highest importance that the faithful should easily understand the sacramental sings, and should frequent with great eagerness those sacraments which were instituted to nourish the Christian life. (Vatican Council II. Constitution Sacrosanctum Concilium, no. 59, December 4, 1963)

For at the beginning of the human race the woman was made of a rib taken from the side of the man while he slept; for it seemed fit that even then Christ and His Church should be foreshadowed in this event. For that sleep of the man was the death of Christ, whose side, as He hung lifeless upon the cross, was pierced with a spear, and there flowed from it blood and water, and these we know to be the sacraments by which the Church is ‘built up’. (Saint Augustine of Hippo. City of God, Book XXII, Ch. 17)

The apostles and their successors are God’s vicars in governing the Church which is built on faith and the sacraments of faith. Wherefore, just as they may not institute another Church, so neither may they deliver another faith, nor institute other sacraments: on the contrary, the Church is said to be built up with the sacraments ‘which flowed from the side of Christ while hanging on the Cross.’ (Saint Thomas Aquinas. Summa Theologica III, q. 64, a. 2, ad. 3)

The exposition of every part of Christian doctrine demands knowledge and industry on the part of the pastor. But instruction on the Sacraments, which, by the ordinance of God, are a necessary means of salvation and a plenteous source of spiritual advantage, demands in a special manner his talents and industry. By accurate and frequent instruction (on the Sacraments) the faithful will be enabled to approach worthily and with salutary effect these inestimable and most holy institutions; and the priests will not depart from the rule laid down in the divine prohibition: Give not that which is holy to dogs: neither cast ye your pearls before swine. (Catechism of Trent, no. 2000)

Now he is in bondage to a sign who uses, or pays homage to, any significant object without knowing what it signifies: he, on the other hand, who either uses or honors a useful sign divinely appointed, whose force and significance he understands, does not honor the sign which is seen and temporal, but that to which all such signs refer. […] But at the present time, after that the proof of our liberty has shone forth so clearly in the resurrection of our Lord, we are not oppressed with the heavy burden of attending even to those signs which we now understand, but our Lord Himself, and apostolic practice, have handed down to us a few rites in place of many, and these at once very easy to perform, most majestic in their significance, and most sacred in the observance; such, for example, as the sacrament of baptism, and the celebration of the body and blood of the Lord. And as soon as any one looks upon these observances he knows to what they refer, and so reveres them not in carnal bondage, but in spiritual freedom. Now, as to follow the letter, and to take signs for the things that are signified by them, is a mark of weakness and bondage; so to interpret signs wrongly is the result of being misled by error. He, however, who does not understand what a sign signifies, but yet knows that it is a sign, is not in bondage. And it is better even to be in bondage to unknown but useful signs than, by interpreting them wrongly, to draw the neck from under the yoke of bondage only to insert it in the coils of error. (Saint Augustine of Hippo. On Christian Doctrine, Book III, Ch. 9, no. 13)

But if anyone who has it in his power to receive baptism within the Catholic Church prefers, from some perversity of mind, to be baptized in schism, even if he afterwards bethinks himself to come to the Catholic Church, because he is assured that there that sacrament will profit him, which can indeed be received but cannot profit elsewhere, beyond all question he is perverse, and guilty of sin, and that the more flagrant in proportion as it was committed wilfully. For that he entertains no doubt that the sacrament is rightly received in the Church, is proved by his conviction that it is there that he must look for profit even from what he has received elsewhere. There are two propositions, moreover, which we affirm–that baptism exists in the Catholic Church, and that in it alone can it be rightly received […] Further, if any one fails to understand how it can be that we assert that the sacrament is not rightly conferred among the Donatists, while we confess that it exists among them, let him observe that we also deny that it exists rightly among them, just as they deny that it exists rightly among those who quit their communion. Let him also consider the analogy of the military mark, which, though it can both be retained, as by deserters, and, also be received by those who are not in the army, yet ought not to be either received or retained outside its ranks; and, at the same time, it is not changed or renewed when a man is enlisted or brought back to his service. (Saint Augustine of Hippo. On Baptism, Book 1, Ch. 2 – 3, no. 4 – 5)

However, we must distinguish between the case of those who unwittingly join the ranks of these heretics, under the impression that they are entering the true Church of Christ, and those who know that there is no other Catholic Church save that which, according to the promise, is spread abroad throughout the whole world, and extends even to the utmost limits of the earth; which, rising amid tares, and seeking rest in the future from the weariness of offenses, says in the Book of Psalms, ‘From the end of the earth I cried unto You, while my heart was in weariness: You exalted me on a rock.’ But the rock was Christ, in whom the apostle says that we are now raised up, and set together in heavenly places, though not yet actually, but only in hope (Eph 2:6). And so the psalm goes on to say, ‘You were my guide, because You have become my hope, a tower of strength from the face of the enemy.’ By means of His promises, which are like spears and javelins stored up in a strongly fortified place, the enemy is not only guarded against, but overthrown, as he clothes his wolves in sheep’s clothing (Mt 7:15), that they may say, ‘Lo, here is Christ, or there’ (Mt 24:23); and that they may separate many from the Catholic city which is built upon a hill, and bring them down to the isolation of their own snares, so as utterly to destroy them. And these men, knowing this, choose to receive the baptism of Christ without the limits of the communion of the unity of Christ’s body, though they intend afterwards, with the sacrament which they have received elsewhere, to pass into that very communion. For they propose to receive Christ’s baptism in antagonism to the Church of Christ, well knowing that it is so even on the very day on which they receive it. And if this is a sin, who is the man that will say, Grant that for a single day I may commit sin? For if he proposes to pass over to the Catholic Church, I would fain ask why. What other answer can he give, but that it is ill to belong to the party of Donatus, and not to the unity of the Catholic Church? Just so many days, then, as you commit this ill, of so many days’ sin are you going to be guilty. And it may be said that there is greater sin in more days’ commission of it, and less in fewer; but in no wise can it be said that no sin is committed at all. But what is the need of allowing this accursed wrong for a single day, or a single hour? For the man who wishes this license to be granted him, might as well ask of the Church, or of God Himself, that for a single day he should be permitted to apostatize. For there is no reason why he should fear to be an apostate for a day, if he does not shrink from being for that time a schismatic or a heretic. (Saint Augustine of Hippo. On Baptism, Book 1, Ch. 4, no. 5)

For first of all the Lord gave that power to Peter, upon whom He built the Church, and whence He appointed and showed the source of unity-the power, namely, that whatsoever he loosed on earth should be loosed in heaven. And after the resurrection, also, He speaks to the apostles, saying, ‘As the Father hath sent me, even so I send you. And when He had said this, He breathed on them, and saith, unto them, Receive ye the Holy Ghost: whosesoever sins ye remit, they are remitted unto them; and whosesoever sins ye retain, they are retained.’ Whence we perceive that only they who are set over the Church and established in the Gospel law, and in the ordinance of the Lord, are allowed to baptize and to give remission of sins; but that without, nothing can either be bound or loosed, where there is none who can either bind or loose anything. (Saint Cyprian of Carthage. Epistle LXXII to Ubaianus, concerning the baptism of heretics, no. 7)

But we who hold the head and root of the one Church know, and trust for certain, that nothing is lawful there outside the Church, and that the baptism which is one is among us, […] Therefore we ought to consider their faith who believe without, whether in respect of the same faith they can obtain any grace. For if we and heretics have one faith, we may also have one grace. […] confess the same Father, the same Son, the same Holy Ghost, the same Church with us, they may also have one baptism if they have also one faith. […] moreover, with the other heretics nay, with them there is nothing but perfidy, and blasphemy, and contention, which is hostile to holiness and truth. How then can one who is baptized among them seem to have obtained mission of sins, and the grace of the divine mercy, by his faith, when he has not the truth of the faith itself? For if, as some suppose, one could receive anything abroad out of the Church according to his faith, certainly he has received what he believed; but if he believes what is false, he could not receive what is true; but rather he has received things adulterous and profane, according to what he believed. This matter of profane and adulterous baptism Jeremiah the prophet plainly rebukes, saying, ‘Why do they who afflict me prevail? My wound is hard; whence shall I be healed? while it has indeed become unto me as deceitful water which has no faithfulness’ (Jer 15:18). The Holy Spirit makes mention by the prophet of deceitful water which has no faithfulness. What is this deceitful and faithless water? Certainly that which falsely assumes the resemblance of baptism, and frustrates the grace of faith by a shadowy pretence. (Saint Cyprian of Carthage. Epistle LXXII to Ubaianus, concerning the baptism of heretics, no. 2.4 – 6)

It is a good soldier’s duty to defend the camp of his general against rebels and enemies. It is the duty of an illustrious leader to keep the standards entrusted to him. It is written, ‘The Lord thy God is a jealous God’ (Deut 4:24). We who have received the Spirit of God ought to have a jealousy for the divine faith; with such a jealousy as that wherewith Phineas both pleased God and justly allayed His wrath when He was angry, and the people were perishing. Why do we receive as allowed an adulterous and alien church, a foe to the divine unity, when we know only one Christ and His one Church? The Church, setting forth the likeness of paradise, includes within her walls fruit-bearing trees, whereof that which does not bring forth good fruit is cut off and is cast into the fire. These trees she waters with four rivers, that is, with the four Gospels, wherewith, by a celestial inundation, she bestows the grace of saving baptism. Can anyone water from the Church’s fountains who is not within the Church? Can one impart those wholesome and saving draughts of paradise to any one if he is perverted, and of himself condemned, and banished outside the fountains of paradise, and has dried up and failed with the dryness of an eternal thirst? (Saint Cyprian of Carthage. Epistle LXXII to Ubaianus, concerning the baptism of heretics, no. 10)

Regenerated as ‘Children in the Son’, the baptized are inseparably joined together as ‘members of Christ and members of the body of the Church’, as the Council of Florence teaches. Baptism symbolizes and brings about a mystical but real incorporation into the crucified and glorious body of Christ. […] In the words of Saint Paul we find again the faithful echo of the teaching of Jesus himself, which reveals the mystical unity of Christ with his disciples and the disciples with each other, presenting it as an image and extension of that mystical communion that binds the Father to the Son and the Son to the Father in the bond of love, the Holy Spirit (cf. Jn 17:21). (John Paul II. Apostolic exhortation Christifideles laici, no. 11–12)

Men are bound to that without which they cannot obtain salvation. Now it is manifest that no one can obtain salvation but through Christ; wherefore the Apostle says (Rom 5:18): ‘As by the offense of one unto all men unto condemnation; so also by the justice of one, unto all men unto justification of life.’ But for this end is Baptism conferred on a man, that being regenerated thereby, he may be incorporated in Christ, by becoming His member: wherefore it is written (Gal 3:27): ‘As many of you as have been baptized in Christ, have put on Christ.’ Consequently it is manifest that all are bound to be baptized: and that without Baptism there is no salvation for men. (Saint Thomas Aquinas. Summa Theologica III, q. 68, a.1)

Behold what you have received! Therefore, just as you see that the bread which was made is one mass, so may you also be one Body by loving one another, by having one faith, one hope, and an undivided charity. When heretics receive this Sacrament, they receive testimony against themselves, because they seek division, while this bread indicates unity. (Saint Augustine of Hippo. Sermon 229, no. 2)

He then who is in the unity of Christ’s body (that is to say, in the Christian membership), of which body the faithful have been wont to receive the sacrament at the altar, that man is truly said to eat the body and drink the blood of Christ. And consequently heretics and schismatics being separate from the unity of this body, are able to receive the same sacrament, but with no profit to themselves–nay, rather to their own hurt, so that they are rather more severely judged than liberated after some time. For they are not in that bond of peace which is symbolized by that sacrament. […] In fine, He Himself, when He says, ‘He that eats my flesh and drinks my blood, dwells in me, and I in him’ (Jn 6:56), shows what it is in reality, and not sacramentally, to eat His body and drink His blood; for this is to dwell in Christ, that He also may dwell in us. So that it is as if He said, He that dwells not in me, and in whom I do not dwell, let him not say or think that he eats my body or drinks my blood. Accordingly, they who are not Christ’s members do not dwell in Him. And they who make themselves members of a harlot, are not members of Christ unless they have penitently abandoned that evil, and have returned to this good to be reconciled to it. (Saint Augustine of Hippo. City of God, Book XXI, Ch. 25)

And therefore receive and eat the body of Christ, yes, you that have become members of Christ in the body of Christ; receive and drink the blood of Christ. In order not to be scattered and separated, eat what binds you together; in order not to seem cheap in your own estimation, drink the price that was paid for you. […] So then, having life in him, you will be in one flesh with him. This sacrament, after all, doesn’t present you with the body of Christ in such a way as to divide you from it. […] You receive worthily, however, if you avoid the yeast of bad doctrine, in order to be unleavened loaves of sincerity and truth (1Cor 5:8). (Saint Augustine of Hippo. Sermon 228B. The Paschal Sacraments, no. 3 – 5)

Shall I say something more fearful. It is not so grievous a thing for the energumens to be within, as for such as these, whom Paul affirms to trample Christ under foot, and to ‘account the blood of the covenant unclean, and to do despite to the grace of the Spirit.’ For he that has fallen into sin and draws near, is worse than one possessed with a devil. For they, because they are possessed are not punished, but those, when they draw near unworthily, are delivered over to undying punishment. Let us not therefore drive away these only, but all without exception, whomsoever we may see coming unworthily. Let no one communicate who is not of the disciples. Let no Judas receive, lest he suffer the fate of Judas. (Saint John Chrysostom. Homilies on the Gospel of Saint Matthew, Homily 82, no. 6)

The answer is that there are two ways of receiving this sacrament, namely, spiritually and sacramentally. Therefore, some receive sacramentally and spiritually, namely, those who receive this sacrament in such a way that they also share in the reality res of the sacrament, namely, charity through which ecclesial unity exists. To such the Lord’s words apply: ‘He that eats me will live because of me.’ But some receive only sacramentally, namely, those who receive this sacrament in such a way that they do not have the res reality of the sacrament, i.e., charity. To these are applied the words spoken here: ‘He that eats and drinks unworthily eats and drinks judgment upon himself.’ Besides these two ways by which the sacrament is taken, there is a third way, by which one eats per accidens, namely, when it is taken not as a sacrament. This can happen in three ways: in one way, as when a believer receives the consecrated host, which he does not believe is consecrated: such a one has the habit of receiving this sacrament, but he does not use it actually as a sacrament. In another way, as when an unbeliever receives the consecrated host, but he has no faith about this sacrament: such a person does not have the habit of using this sacrament. (Saint Thomas Aquinas. Commentary on the First Epistle to the Corinthians, no. 698, 1Cor 11:27–34)

He wished, furthermore, that this be a pledge of our future glory and of everlasting happiness, and thus be a symbol of that one ‘body’ of which He Himself is the ‘head’ (1Cor 11:23 Eph 5:23), and to which He wished us to be united, as members, by the closest bond of faith, hope, and charity, that we might ‘all speak the same thing and there might be no schisms among us’ (cf. 1Cor 1:10). (Denzinger-Hünermann 1638. Julius III, Council of Trent, Session XIII, October 11, 1551)

The Church is a ‘communion of saints’: this expression refers first to the ‘holy things’ (sancta), above all the Eucharist, by which ‘the unity of believers, who form one body in Christ, is both represented and brought about’ (LG 3). (Catechism of the Catholic Church, no. 960)

This is why Christian antiquity used the same words, Corpus Christi, to designate Christ’s body born of the Virgin Mary, his eucharistic body and his ecclesial body. This clear datum of the tradition helps us to appreciate the inseparability of Christ and the Church. The Lord Jesus, by offering himself in sacrifice for us, in his gift effectively pointed to the mystery of the Church. It is significant that the Second Eucharistic Prayer, invoking the Paraclete, formulates its prayer for the unity of the Church as follows: ‘may all of us who share in the body and blood of Christ be brought together in unity by the Holy Spirit.’ These words help us to see clearly how the res of the sacrament of the Eucharist is the unity of the faithful within ecclesial communion. The Eucharist is thus found at the root of the Church as a mystery of communion. (Benedict XVI. Apostolic exhortation Sacramentum Caritatis, no. 15, February 22, 2007)

But although there are two elements, as bread and wine, of which the entire Sacrament of the Eucharist is constituted, yet guided by the authority of the Church, we confess that this is not many Sacraments, but only one. […] Moreover, by virtue of the Sacrament, one mystical body is effected; hence, that the Sacrament itself may correspond to the thing which it effects, it must be one. (Catechism of Trent, no. 2300)

In this sacrament, as in the others, that which is a sacrament is a sign of the reality of the sacrament. Now there is a twofold reality of this sacrament, as stated above (q. 73, a. 6): one which is signified and contained, namely, Christ Himself; while the other is signified but not contained, namely, Christ’s mystical body, which is the fellowship of the saints. Therefore, whoever receives this sacrament, expresses thereby that he is made one with Christ, and incorporated in His members. (Saint Thomas Aquinas. Summa Theologica III, q. 80, a.4)

This sacrament has a threefold significance. One with regard to the past, inasmuch as it is commemorative of our Lord’s Passion, which was a true sacrifice, as stated above (q. 48, a. 3), and in this respect it is called a ‘Sacrifice.’ With regard to the present it has another meaning, namely, that of Ecclesiastical unity, in which men are aggregated through this Sacrament; and in this respect it is called ‘Communion’ or ‘Synaxis’. For Damascene says (De Fide Orth. IV) that ‘it is called Communion because we communicate with Christ through it, both because we partake of His flesh and Godhead, and because we communicate with and are united to one another through it.’ (Saint Thomas Aquinas. Summa Theologica III, q. 73, a. 4)

So then the Eucharist is our daily bread; but let us in such wise receive it, that we be not refreshed in our bodies only, but in our souls. For the virtue which is apprehended there, is unity, that gathered together into His body, and made His members, we may be what we receive. Then will it be indeed our daily bread. (Saint Augustine of Hippo. Sermon 7, On the Lord’s prayer no. 7)

[Condemned proposition:] 15 – Great is the error of those who approach the sacrament of the Eucharist relying on this, that they have confessed, that they are not conscious of any mortal sin, that they have sent their prayers on ahead and made preparations; all these eat and drink judgment to themselves. But if they believe and trust that they will attain grace, then this faith alone makes them pure and worthy.
[Censure]: ‘All and each of the above mentioned articles or errors, so to speak, as set before you, we condemn, disapprove, and entirely reject as respectively heretical, or scandalous, or false, or offensive to pious ears, or seductive of simple minds, and in opposition to Catholic truth.’ (Denzinger-Hünermann 1465. 1491. Bull Exurge Domine, June 15, 1520)

What is ‘The deposit’? That which has been entrusted to you, not that which you have yourself devised: a matter not of wit, but of learning; not of private adoption, but of public tradition; a matter brought to you, not put forth by you, wherein you are bound to be not an author but a keeper, not a teacher but a disciple, not a leader but a follower. ‘Keep the deposit.’ Preserve the talent of Catholic Faith inviolate, unadulterate. That which has been entrusted to you, let it continue in your possession, let it be handed on by you. You have received gold; give gold in turn. Do not substitute one thing for another. Do not for gold impudently substitute lead or brass. Give real gold, not counterfeit. (Saint Vincent of Lerins. Commonitory for the Antiquity and Universality of the Catholic Faith, Ch. 22)

‘Profane novelties of words.’ What words are these? Such as have nothing sacred, nothing religious, words utterly remote from the inmost sanctuary of the Church which is the temple of God. Profane novelties of words, that is, of doctrines, subjects, opinions, such as are contrary to antiquity and the faith of the olden time. Which if they be received, it follows necessarily that the faith of the blessed fathers is violated either in whole, or at all events in great part; it follows necessarily that all the faithful of all ages, all the saints, the chaste, the continent, the virgins, all the clergy, Deacons and Priests, so many thousands of Confessors, so vast an army of martyrs, such multitudes of cities and of peoples, so many islands, provinces, kings, tribes, kingdoms, nations, in a word, almost the whole earth, incorporated in Christ the Head, through the Catholic faith, have been ignorant for so long a tract of time, have been mistaken, have blasphemed, have not known what to believe, what to confess. Shun profane novelties of words, which to receive and follow was never the part of Catholics; of heretics always was. (Saint Vincent of Lerins. Commonitory for the Antiquity and Universality of the Catholic Faith, Ch. 24)

This being the case, he is the true and genuine Catholic who loves the truth of God, who loves the Church, who loves the Body of Christ, who esteems divine religion and the Catholic Faith above everything, above the authority, above the regard, above the genius, above the eloquence, above the philosophy, of every man whatsoever; who sets light by all of these, and continuing steadfast and established in the faith, resolves that he will believe that, and that only, which he is sure the Catholic Church has held universally and from ancient time; but that whatsoever new and unheard-of doctrine he shall find to have been furtively introduced by some one or another, besides that of all, or contrary to that of all the saints, this, he will understand, does not pertain to religion, but is permitted as a trial. (Saint Vincent of Lerins. Commonitory for the Antiquity and Universality of the Catholic Faith, Ch. 20)

But some one will say, perhaps, Shall there, then, be no progress in Christ’s Church? Certainly; all possible progress. For what being is there, so envious of men, so full of hatred to God, who would seek to forbid it? Yet on condition that it be real progress, not alteration of the faith. For progress requires that the subject be enlarged n itself, alteration, that it be transformed into something else. The intelligence, then, the knowledge, the wisdom, as well of individuals as of all, as well of one man as of the whole Church, ought, in the course of ages and centuries, to increase and make much and vigorous progress; but yet only in its own kind; that is to say, in the same doctrine, in the same sense, and in the same meaning. The growth of religion in the soul must be analogous to the growth of the body, which, though in process of years it is developed and attains its full size, yet remains still the same. […] In like manner, it behooves Christian doctrine to follow the same laws of progress, so as to be consolidated by years, enlarged by time, refined by age, and yet, withal, to continue uncorrupt and unadulterate, complete and perfect in all the measurement of its parts, and, so to speak, in all its proper members and senses, admitting no change, no waste of its distinctive property, no variation in its limits. (Saint Vincent of Lerins. Commonitory for the Antiquity and Universality of the Catholic Faith, Ch. 20)

Shall We suffer, what would indeed be iniquitous, the truth, and a truth divinely revealed, to be made a subject for compromise? For here there is question of defending revealed truth. Jesus Christ sent His Apostles into the whole world in order that they might permeate all nations with the Gospel faith, and, lest they should err, He willed beforehand that they should be taught by the Holy Ghost: has then this doctrine of the Apostles completely vanished away, or sometimes been obscured, in the Church, whose ruler and defense is God Himself? If our Redeemer plainly said that His Gospel was to continue not only during the times of the Apostles, but also till future ages, is it possible that the object of faith should in the process of time become so obscure and uncertain, that it would be necessary to-day to tolerate opinions which are even incompatible one with another? If this were true, we should have to confess that the coming of the Holy Ghost on the Apostles, and the perpetual indwelling of the same Spirit in the Church, and the very preaching of Jesus Christ, have several centuries ago, lost all their efficacy and use, to affirm which would be blasphemy. (Pius XI. Encyclical Mortalium animos, no. 8, January 6, 1928)

How so great a variety of opinions can make the way clear to effect the unity of the Church We know not; that unity can only arise from one teaching authority, one law of belief and one faith of Christians. But We do know that from this it is an easy step to the neglect of religion or indifferentism and to modernism, as they call it. Those, who are unhappily infected with these errors, hold that dogmatic truth is not absolute but relative, that is, it agrees with the varying necessities of time and place and with the varying tendencies of the mind, since it is not contained in immutable revelation, but is capable of being accommodated to human life. (Pius XI. Encyclical Mortalium animos, no. 9, January 6, 1928)

‘How do we acquire a living faith, a truly Catholic faith, a faith that is practical, lively and effective?’ Faith, ultimately, is a gift. […] We do not ‘have’ faith, in the sense that it is primarily God who gives it to us. Nor do we ‘have’ it either, in the sense that it must not be invented by us. (Benedict XVI. Meeting with the members of the Roman Clergy, March 2, 2006)

Such an exhortation seems to us to be of capital importance, for the presentation of the Gospel message is not an optional contribution for the Church. It is the duty incumbent on her by the command of the Lord Jesus, so that people can believe and be saved. This message is indeed necessary. It is unique. It cannot be replaced. It does not permit either indifference, syncretism or accommodation. It is a question of people’s salvation. It is the beauty of the Revelation that it represents. It brings with it a wisdom that is not of this world. It is able to stir up by itself faith – faith that rests on the power of God. It is truth. It merits having the apostle consecrate to it all his time and all his energies, and to sacrifice for it, if necessary, his own life. (Paul VI. Apostolic exhortation Evangelii nuntiandi, no. 5, December 8, 1975)

Here it is not a question of altering the deposit of faith, changing the meaning of dogmas, eliminating essential words from them, accommodating truth to the preferences of a particular age, or suppressing certain articles of the Creed under the false pretext that they are no longer understood today. The unity willed by God can be attained only by the adherence of all to the content of revealed faith in its entirety. In matters of faith, compromise is in contradiction with God who is Truth. In the Body of Christ, ‘the way, and the truth, and the life’ (Jn 14:6), who could consider legitimate a reconciliation brought about at the expense of the truth? […] A ‘being together’ which betrayed the truth would thus be opposed both to the nature of God who offers his communion and to the need for truth found in the depths of every human heart. (John Paul II. Encyclical Ut unum sint, no. 18, May 25, 1995)

Love for the truth is the deepest dimension of any authentic quest for full communion between Christians. […] Full communion of course will have to come about through the acceptance of the whole truth into which the Holy Spirit guides Christ’s disciples. Hence all forms of reductionism or facile ‘agreement’ must be absolutely avoided. (John Paul II. Encyclical Ut unum sint, no. 36, May 25, 1995)

Even on the plea of promoting unity it is not allowed to dissemble one single dogma; for, as the Patriarch of Alexandria warns us, ‘although the desire of peace is a noble and excellent thing, yet we must not for its sake neglect the virtue of loyalty in Christ.’ […] The only successful method will be that which bases harmony and agreement among Christ’s faithful ones upon all the truths, and the whole of the truths, which God has revealed. (Pius XII. Encyclical Orientalis Ecclesiae, no. 1, April 9, 1944)

We advise the reconciliation and union with the Church of Rome; and We mean a perfect and complete union, such as could not subsist in any way if nothing else was brought about but a certain kind of agreement in the Tenets of Belief and an intercourse of Fraternal love. The True Union between Christians is that which Jesus Christ, the Author of the Church, instituted and desired, and which consists in a Unity of Faith and Unity of Government. (Leo XIII. Encyclical Praeclara gratulationis publicae, June 20, 1894)

Catholic doctrine tells us that the primary duty of charity does not lie in the toleration of false ideas, however sincere they may be, nor in the theoretical or practical indifference towards the errors and vices in which we see our brethren plunged. […] If, as We desire with all Our heart, the highest possible peak of well being for society and its members is to be attained through fraternity or, as it is also called, universal solidarity, all minds must be united in the knowledge of Truth, all wills united in morality, and all hearts in the love of God and His Son Jesus Christ. (Pius X. Encyclical Notre charge apostolique, no. 22 – 23, August 23, 1910)

Vatican Council I (Ecumenical XX)

But the Catholic Church professes that this faith, which ‘is the beginning of human salvation’ [cf. no. 801], is a supernatural virtue by which we, with the aid and inspiration of the grace of God, believe that the things revealed by Him are true, not because the intrinsic truth of the revealed things has been perceived by the natural light of reason, but because of the authority of God Himself who reveals them, who can neither deceive nor be deceived [can. 2]. (Denzinger-Hünermann 3008. Vatican Council I, Session III, April 24, 1870)

Saint Thomas Aquinas

If we take faith as a habit, we can consider it in two ways. First on the part of the object, and thus there is one faith. Because the formal object of faith is the First Truth, by adhering to which we believe whatever is contained in the faith. […] If, on the other hand, we take faith for that which is believed, then, again, there is one faith, since what is believed by all is one same thing: for though the things believed, which all agree in believing, be diverse from one another, yet they are all reduced to one. (Saint Thomas Aquinas. Summa Theologica II-II, q. 4, a. 6)

Congregation for the Doctrine of the Faith

Belief, in the other religions, is that sum of experience and thought that constitutes human wisdom and religious aspiration, not an adhesion to God who reveals and to the truth which he reveals

‘Faith is first of all a personal adherence of man to God. At the same time, and inseparably, it is a free assent to the whole truth that God has revealed’. Faith, therefore, as ‘a gift of God’ and as ‘a supernatural virtue infused by him’, involves a dual adherence: to God who reveals and to the truth which he reveals, out of the trust which one has in him who speaks. Thus, ‘we must believe in no one but God: the Father, the Son and the Holy Spirit’. For this reason, the distinction between theological faith and belief in the other religions, must be firmly held. If faith is the acceptance in grace of revealed truth, which ‘makes it possible to penetrate the mystery in a way that allows us to understand it coherently’, then belief, in the other religions, is that sum of experience and thought that constitutes the human treasury of wisdom and religious aspiration, which man in his search for truth has conceived and acted upon in his relationship to God and the Absolute. This distinction is not always borne in mind in current theological reflection. Thus, theological faith (the acceptance of the truth revealed by the One and Triune God) is often identified with belief in other religions, which is religious experience still in search of the absolute truth and still lacking assent to God who reveals himself. This is one of the reasons why the differences between Christianity and the other religions tend to be reduced at times to the point of disappearance. (Congregation for the Doctrine of the Faith, Declaration Dominus Iesus, no. 7, August 6, 2000)

Saint Thomas Aquinas

Neither living nor lifeless faith remains in a heretic who disbelieves one article of faith. The reason of this is that the species of every habit depends on the formal aspect of the object, without which the species of the habit cannot remain. Now the formal object of faith is the First Truth, as manifested in Holy Writ and the teaching of the Church, which proceeds from the First Truth. Consequently whoever does not adhere, as to an infallible and Divine rule, to the teaching of the Church, which proceeds from the First Truth manifested in Holy Writ, has not the habit of faith, but holds that which is of faith otherwise than by faith. Even so, it is evident that a man whose mind holds a conclusion without knowing how it is proved, has not scientific knowledge, but merely an opinion about it. Now it is manifest that he who adheres to the teaching of the Church, as to an infallible rule, assents to whatever the Church teaches; otherwise, if, of the things taught by the Church, he holds what he chooses to hold, and rejects what he chooses to reject, he no longer adheres to the teaching of the Church as to an infallible rule, but to his own will. Hence it is evident that a heretic who obstinately disbelieves one article of faith, is not prepared to follow the teaching of the Church in all things; but if he is not obstinate, he is no longer in heresy but only in error. Therefore it is clear that such a heretic with regard to one article has no faith in the other articles, but only a kind of opinion in accordance with his own will. (Saint Thomas Aquinas. Summa Theologica, II-II, q. 5, a.3)

Saint Thomas Aquinas

Now, whoever believes, assents to someone’s words; so that, in every form of unbelief, the person to whose words assent is given seems to hold the chief place and to be the end as it were; while the things by holding which one assents to that person hold a secondary place. Consequently he that holds the Christian faith aright, assents, by his will, to Christ, in those things which truly belong to His doctrine. Accordingly there are two ways in which a man may deviate from the rectitude of the Christian faith. First, because he is unwilling to assent to Christ: and such a man has an evil will, so to say, in respect of the very end. This belongs to the species of unbelief in pagans and Jews. Secondly, because, though he intends to assent to Christ, yet he fails in his choice of those things wherein he assents to Christ, because he chooses not what Christ really taught, but the suggestions of his own mind. Therefore heresy is a species of unbelief, belonging to those who profess the Christian faith, but corrupt its dogmas. (Saint Thomas Aquinas. Summa Theologica II-II, q. 11, a.1)

Saint Thomas Aquinas

Every sin consists formally in aversion from God, as stated above (I-II, q. 71, a. 6; q. 73, a. 3 ad 3). Hence the more a sin severs man from God, the graver it is. Now man is more than ever separated from God by unbelief, because he has not even true knowledge of God: and by false knowledge of God, man does not approach Him, but is severed from Him. Nor is it possible for one who has a false opinion of God, to know Him in any way at all, because the object of his opinion is not God. Therefore it is clear that the sin of unbelief is greater than any sin that occurs in the perversion of morals. This does not apply to the sins that are opposed to the theological virtues, as we shall stated further on (II-II q. 20, a.3; q. 34, a. 2, ad 2; q. 39, a. 2, ad 3). (Saint Thomas Aquinas. Summa Theologica II-II, q. 10, a.3)

Saint Thomas Aquinas

It is written (2Pet 2:21): ‘It had been better for them not to have known the way of justice, than after they have known it, to turn back.’ Now the heathens have not known the way of justice, whereas heretics and Jews have abandoned it after knowing it in some way. Therefore theirs is the graver sin. I answer that, As stated above (a. 5), two things may be considered in unbelief. One of these is its relation to faith: and from this point of view, he who resists the faith after accepting it, sins more grievously against faith, than he who resists it without having accepted it, even as he who fails to fulfil what he has promised, sins more grievously than if he had never promised it. In this way the unbelief of heretics, who confess their belief in the Gospel, and resist that faith by corrupting it, is a more grievous sin than that of the Jews, who have never accepted the Gospel faith. Since, however, they accepted the figure of that faith in the Old Law, which they corrupt by their false interpretations, their unbelief is a more grievous sin than that of the heathens, because the latter have not accepted the Gospel faith in any way at all. The second thing to be considered in unbelief is the corruption of matters of faith. In this respect, since heathens err on more points than Jews, and these in more points than heretics, the unbelief of heathens is more grievous than the unbelief of the Jews, and that of the Jews than that of the heretics, except in such cases as that of the Manichees, who, in matters of faith, err even more than heathens do. Of these two gravities the first surpasses the second from the point of view of guilt; since, as stated above (a. 1) unbelief has the character of guilt, from its resisting faith rather than from the mere absence of faith, for the latter as was stated (a. 1) seems rather to bear the character of punishment. Hence, speaking absolutely, the unbelief of heretics is the worst. (Saint Thomas Aquinas. Summa Theologica II-II, q. 10, a. 6)

At the outset I must deny that there are seven sacraments, and hold for the present to but three – baptism, penance and the bread. These three have been subjected to a miserable captivity by the Roman curia, and the Church has been deprived of all her liberty. To be sure, if I desired to use the term in its scriptural sense, I should allow but a single sacrament, with three sacramental signs. But of this I shall treat more fully at the proper time.
Note: The only sacrament, then, would be the word of God fulfilled in Christ! (Martin Luther. A prelude on the Babylonian Captivity of the Church, 1520)

I wonder what could have possessed them to make a sacrament of confirmation out of the laying on of hands […] instead of this, sacraments that have been divinely instituted, among which we see no reason for numbering confirmation. (Martin Luther. A prelude on the Babylonian Captivity of the Church, 1520)

Of this sacrament the Church of Christ knows nothing; it is an invention of the pope’s church. Not only is there nowhere any promise of grace attached to it, but there is not the least mention of it in the whole New Testament. Now it is ridiculous to put forth as a sacrament of God that which cannot be proved to have been instituted by God. I do not hold that this rite, which has been observed for so many centuries, should be condemned; but in sacred things I am opposed to the invention of human fictions, nor is it right to give out as divinely instituted what was not divinely instituted, lest we become a laughing-stock to our opponents. (Martin Luther. A prelude on the Babylonian Captivity of the Church, 1520)

For whatever issues from baptism, may boast that it has been consecrated priest, bishop, and Pope, although it does not beseem everyone to exercise these offices. For, since we are all priests alike, no man may put himself forward, or take upon himself, without our consent and election, to do that which we have all alike power to do. For, if a thing is common to all, no man may take it to himself without the wish and command of the community. And if it should happen that a man were appointed to one of these offices and deposed for abuses, he would be just what he was before. Therefore a priest should be nothing in Christendom but a functionary; as long as he holds his office, he has precedence of others; if he is deprived of it, he is a peasant and a citizen like the rest. Therefore a priest is verily no longer a priest after deposition. But now they have invented characters indelebiles, and pretend that a priest after deprivation still differs from a simple layman. They even imagine that a priest can never be anything but a priest, that is, that he can never become a layman. All this is nothing but mere talk and ordinance of human invention. (Martin Luther. To the Christian nobility of the German nation respecting the Reformation of the Christian estate, 1520)

Hence, I have no doubt but that everyone is absolved from his hidden sins when he has made confession, either of his own accord or after being rebuked, has sought pardon and amended his ways, privately before any brother, however much the violence of the pontiffs may rage against it; for Christ has given to every one of His believers the power to absolve even open sins. Add yet this little point: If any reservation of hidden sins were valid, so that one could not be saved unless they were forgiven, then a man’s salvation would be prevented most of all by those aforementioned good works and idolatries, which are nowadays taught by the popes. But if these most grievous sins do not prevent one’s salvation, how foolish it is to reserve those lighter sins! Verily, it is the foolishness and blindness of the pastors that produce these monstrous things in the Church. Therefore I would admonish these princes of Babylon and bishops of Bethaven (Hos 4:15; Hos 10:5) to refrain from reserving any cases whatsoever. Let them, moreover, permit all brothers and sisters freely to hear the confession of hidden sins, so that the sinner may make his sins known to whomever he will and seek pardon and comfort, that is, the word of Christ, by the mouth of his neighbor. For with these presumptions of theirs they only ensnare the consciences of the weak without necessity, establish their wicked despotism, and fatten their avarice on the sins and ruin of their brethren. Thus they stain their hands with the blood of souls, sons are devoured by their parents, Ephraim devours Juda, and Syria Israel with open mouth, as Isaiah said. (Isaiah 9:20) (Martin Luther. A prelude on the Babylonian Captivity of the Church, 1520)

Not only is marriage regarded as a sacrament without the least warrant of Scripture, but the very traditions which extol it as a sacrament have turned it into a farce. […]Christ and the Church are, therefore, a mystery, that is, a great and secret thing, which it was possible and proper to represent by marriage as by a certain outward allegory, but that was no reason for their calling marriage a sacrament. […] Therefore we grant that marriage is a type of Christ and the Church, and a sacrament, yet not divinely instituted but invented by men in the Church, carried away by their ignorance both of the word and of the thing. Which ignorance, since it does not conflict with the faith, is to be charitably borne with, just as many other practices of human weakness and ignorance are borne within the Church, so long as they do not conflict with the faith and with the Word of God. (Martin Luther. A prelude on the Babylonian Captivity of the Church, 1520)

With all this extolling of married life, however, I have not meant to ascribe to nature a condition of sinlessness. On the contrary, I say that flesh and blood, corrupted through Adam, is conceived and born in sin, as Psalm 51 says [Ps 51:5]. Intercourse is never without Sin; but God excuses it by his grace because the estate of marriage is his work, and he preserves in and through the sin all that good which he has implanted and blessed in marriage. (Martin Luther. The estate of marriage, 1522)

The third case for divorce is that in which one of the parties deprives and avoids the other, refusing to fulfil the conjugal duty or to live with the other person. For example, one finds many a stubborn wife like that who will not give in, and who cares not a whit whether her husband falls into the sin of unchastity ten times over. Here it is time for the husband to say, ‘If you will not, another will; the maid will come if the wife will not.’ Only first the husband should admonish and warn his wife two or three times, and let the situation be known to others so that her stubbornness becomes a matter of common knowledge and is rebuked before the congregation. If she still refuses, get rid of her; take an Esther and let Vashti go, as King Ahasuerus did (Esther 1:17). (Martin Luther. The estate of marriage, 1522)

Don’t let yourself be fooled on this score, even if you should make ten oaths, vows, covenants, and adamantine or ironclad pledges. For as you cannot solemnly promise that you will not be a man or a woman (and if you should make such a promise it would be foolishness and of no avail since you cannot make yourself something other than what you are). […] And should you make such a promise, it too would be foolishness and of no avail, for to produce seed and to multiply is a matter of God’s ordinance [geschöpffe], not your power. From this you can now see the extent of the validity of all cloister vows. No vow of any youth or maiden is valid before God, […] Therefore, priests, monks, and nuns are duty-bound to forsake their vows whenever they find that God’s ordinance to produce seed and to multiply is powerful and strong within them. They have no power by any authority, law, command, or vow to hinder this which God has created within them. If they do hinder it, however, you may be sure that they will not remain pure but inevitably besmirch themselves with secret sins or fornication. For they are simply incapable of resisting the word and ordinance of God within them. Matters will take their course as God has ordained. (Martin Luther. The estate of marriage, 1522)