By enduring agreement the Catholic Church has held and holds that there is a twofold order of knowledge, distinct not only in principle but also in object: (1) in principle, indeed, because we know in one way by natural reason, in another by divine faith; (2) in object, however, because, in addition to things to which natural reason can attain, mysteries hidden in God are proposed to us for belief which, had they not been divinely revealed, could not become known. Wherefore, the Apostle, who testifies that God was known to the Gentiles “by the things that are made” [Rom 1:20], nevertheless, when discoursing about grace and truth which “was made through Jesus Christ” [cf. Jn 1:17] proclaims: “We speak the wisdom of God in a mystery, a wisdom which is hidden, which God ordained before the world, unto our glory, which none of the princes of this world know. […] But to us God hath revealed them by His Spirit For the Spirit searcheth all things, yea the deep things of God” [1Cor 2:7,8,10]. And the Only-begotten Himself “confesses to the Father, because He hath hid these things from the wise and prudent, and hath revealed them to little ones” [cf. Mt 11:25]
And, indeed, reason illustrated by faith, when it zealously, piously, and soberly seeks, attains with the help of God some understanding of the mysteries, and that a most profitable one, not only from the analogy of those things which it knows naturally, but also from the connection of the mysteries among themselves and with the last end of man; nevertheless, it is never capable of perceiving those mysteries in the way it does the truths which constitute its own proper object. For, divine mysteries by their nature exceed the created intellect so much that, even when handed down by revelation and accepted by faith, they nevertheless remain covered by the veil of faith itself, and wrapped in a certain mist, as it were, as long as in this mortal life, “we are absent from the Lord: for we walk by faith and not by sight” [2Cor 5:6 f.],
But, although faith is above reason, nevertheless, between faith and reason no true dissension can ever exist, since the same God, who reveals mysteries and infuses faith, has bestowed on the human soul the light of reason; moreover, God cannot deny Himself, nor ever contradict truth with truth. But, a vain appearance of such a contradiction arises chiefly from this, that either the dogmas of faith have not been understood and interpreted according to the mind of the Church, or deceitful opinions are considered as the determinations of reason. Therefore, “every assertion contrary to the truth illuminated by faith, we define to be altogether false” [Lateran Council V].
Further, the Church which, together with the apostolic duty of teaching, has received the command to guard the deposit of faith, has also, from divine Providence, the right and duty of proscribing “knowledge falsely so called” [1Tim 6:20], “lest anyone be cheated by philosophy and vain deceit” [cf. Col 2:8]. Wherefore, all faithful Christians not only are forbidden to defend opinions of this sort, which are known to be contrary to the teaching of faith, especially if they have been condemned by the Church, as the legitimate conclusions of science, but they shall be altogether bound to hold them rather as errors, which present a false appearance of truth.
And, not only can faith and reason never be at variance with one another, but they also bring mutual help to each other, since right reasoning demonstrates the basis of faith and, illumined by its light, perfects the knowledge of divine things, while faith frees and protects reason from errors and provides it with manifold knowledge. Wherefore, the Church is so far from objecting to the culture of the human arts and sciences, that it aids and promotes this cultivation in many ways. For, it is not ignorant of, nor does it despise the advantages flowing therefrom into human life; nay, it confesses that, just as they have come forth from “God, the Lord of knowledge” [1Sam 2:3], so, if rightly handled, they lead to God by the aid of His grace. And it (the Church) does not forbid disciplines of this kind, each in its own sphere, to use its own principles and its own method; but, although recognizing this freedom, it continually warns them not to fall into errors by opposition to divine doctrine, nor, having transgressed their own proper limits, to be busy with and to disturb those matters which belong to faith.
For, the doctrine of faith which God revealed has not been handed down as a philosophic invention to the human mind to be perfected, but has been entrusted as a divine deposit to the Spouse of Christ, to be faithfully guarded and infallibly interpreted. Hence, also, that understanding of its sacred dogmas must be perpetually retained, which Holy Mother Church has once declared; and there must never be recession from that meaning under the specious name of a deeper understanding “Therefore […] let the understanding, the knowledge, and wisdom of individuals as of all, of one man as of the whole Church, grow and progress strongly with the passage of the ages and the centuries; but let it be solely in its own genus, namely in the same dogma, with the same sense and the same understanding.” [Vincent of Lerins, Commonitorium, 23, 3].
Original Latin text in H. DENZINGER, Enchiridion Simbolorum, definitionum et declarationum de rebus fidei et morum, ed. by P. Hünermann(Freiburg i.B.: Herder, 1991),DH 3001-3020. English translation provided by Welcome to Catholic Church, Harmony Media inc.