But since the Modernists (as they are commonly and rightly called) employ a very clever artifice, namely, to present their doctrines without order and systematic arrangement into one whole, scattered and disjointed one from another, so as to appear to be in doubt and uncertainty, while they are in reality firm and steadfast, it will be of advantage, Venerable Brethren, to bring their teachings together here into one group, and to point out the connexion between them, and thus to pass to an examination of the sources of the errors, and to prescribe remedies for averting the evil. (Pius X. Encyclical Pascendi Dominici gregis, no. 4, September 8, 1907)

They recognise that the three chief difficulties for them are scholastic philosophy, the authority of the fathers and tradition, and the magisterium of the Church, and on these they wage unrelenting war. For scholastic philosophy and theology they have only ridicule and contempt. Whether it is ignorance or fear, or both, that inspires this conduct in them, certain it is that the passion for novelty is always united in them with hatred of scholasticism, and there is no surer sign that a man is on the way to Modernism than when he begins to show his dislike for this system. (Pius X. Encyclical Pascendi Dominici gregis, no. 42, September 8, 1907)

Equal diligence and severity are to be used in examining and selecting candidates for Holy Orders. Far, far from the clergy be the love of novelty! God hates the proud and the obstinate. (Pius X. Encyclical Pascendi Dominici gregis, no. 49, September 8, 1907)

[Condemned proposition:] The method and principles according to which the ancient scholastic doctors treated theology are by no means suited to the necessities of our times and to the progress of the sciences . (Denzinger-Hünermann 2913. Pius IX, Syllabus of the errors of our times, December 8, 1864)

Among the Scholastic Doctors, the chief and master of all towers Thomas Aquinas […] in such a manner that in him there is wanting neither a full array of questions, nor an apt disposal of the various parts, nor the best method of proceeding, nor soundness of principles or strength of argument, nor clearness and elegance of style, nor a facility for explaining what is abstruse. (Leo XIII. Encyclical Aeterni Patris, August 4, 1879)

In order to exercise the prophetic function in the world, the People of God must continually reawaken or ‘rekindle’ its own life of faith (cf. 2Tim 1:6). It does this particularly by contemplating ever more deeply, under the guidance of the Holy Spirit, the contents of the faith itself and by dutifully presenting the reasonableness of the faith to those who ask for an account of it (cf. 1Pet 3:15). (Congregation for the Doctrine of the Faith, Donum veritatis,  no. 5, March 24, 1990)

By its nature, faith appeals to reason because it reveals to man the truth of his destiny and the way to attain it. Revealed truth, to be sure, surpasses our telling. All our concepts fall short of its ultimately unfathomable grandeur (cf. Eph 3:19). Nonetheless, revealed truth beckons reason – God’s gift fashioned for the assimilation of truth – to enter into its light and thereby come to understand in a certain measure what it has believed. Theological science responds to the invitation of truth as it seeks to understand the faith. It thereby aids the People of God in fulfilling the Apostle’s command (cf. 1 Pet 3:15) to give an accounting for their hope to those who ask it. (Congregation for the Doctrine of the Faith, Donum veritatis, no. 5, March 24, 1990)

It is also true that theologians must always have recourse to the sources of divine Revelation; for it is their duty to indicate how what is taught by the living magisterium is found, either explicitly or implicitly, in Sacred Scripture and in divine ‘tradition.’ In addition, both sources of doctrine, divinely revealed, contain so many and such great treasures of truth that they are in fact never exhausted. (Denzinger-Hünermann 3886. Pius XII. Encyclical Humani generis, August 12, 1950)

Therefore, to neglect, or to reject, or to deprive so many great things of their value, which in many instances have been conceived, expressed, and perfected after long labor, by men of no ordinary genius and sanctity, under the watchful eye of the holy Magisterium, and not without the light and guidance of the Holy Spirit for the expression of the truths of faith ever more accurately, so that in their place conjectural notions may be substituted, as well as certain unstable and vague expressions of a new philosophy, which like a flower of the field exists today and will die tomorrow, not only is the highest imprudence, but also makes dogma itself as a reed shaken by the wind. Moreover, the contempt for the words and ideas which the scholastic theologians customarily use, tends to weaken so-called speculative philosophy, which they think is void of true certitude, since it rests on theological reasoning. (Denzinger-Hünermann 3883. Pius XII. Encyclical Humani generis, August 12, 1950)

Surely it is lamentable that those eager for novelty easily pass from a contempt for scholastic theology to a neglect, and even a disrespect for the magisterium of the Church, which supports that theology by its authority. For, this Magisterium is considered by them as a hindrance to progress and an obstacle to science; indeed, by certain non-Catholics it is looked upon as an unjust restraint by which some learned theologians are prevented from pursuing their science. (Denzinger-Hünermann 3884. Pius XII. Encyclical Humani generis, August 12, 1950)