Aquinas on Theology

• “There are two kinds of theology. One follows the reasonable course of inferring divine truths from meanings governing the physical world: it is thus that philosophers, claiming for fundamental philosophy, or metaphysics, the title of the divine science, have discussed theological truths. The other, while appreciating that at present when we are wayfarers we cannot see for ourselves the supreme evidence of divine truths, already begins through infused faith to take after and share in God’s knowledge by cleaving to His fundamental truth for its own sake.” (Exposition of the De Trinitate, 2, 2.)

• “The purpose of theology is threefold: to refute error, to teach sound morals, and to contemplate truth.” (On the Sentences I, Prol. 1, 5.)

• “Theology deserves to be called the highest wisdom, for everything is viewed in light of the first cause.” (Summa Contra Gentes, 2, 4.)

• “This doctrine is especially based upon arguments from authority, inasmuch as its principles are obtained by revelation: thus we ought to believe on the authority of those to whom the revelation has been made. Nor does this take away from the dignity of this doctrine, for although the argument from authority based on human reason is the weakest, yet the argument from authority based on divine revelation is the strongest. But sacred doctrine makes use even of human reason, not, indeed, to prove faith (for thereby the merit of faith would come to an end), but to make clear other things that are put forward in this doctrine. Since therefore grace does not destroy nature but perfects it, natural reason should minister to faith as the natural bent of the will ministers to charity. Hence the Apostle says: "Bringing into captivity every understanding unto the obedience of Christ" (2 Cor 10:5).” (Summa Theologiae, Ia, q. 1, a. 8, ad. 2.)

• “The fact that some happen to doubt about articles of faith is not due to the uncertain nature of the truths, but to the weakness of human intelligence; yet the slenderest knowledge that may be obtained of the highest things is more desirable than the most certain knowledge obtained of lesser things, as is said in de Animalibus xi.” (Summa Theologiae, Ia, q. 1, a. 5, ad 1.)

• “The principles of reason are the foundations of philosophy, the principles of faith are the foundations of Christian theology. The truths of philosophy are more restricted; they cannot be contrary to the truths of faith, but instead offer likenesses and anticipations of them. Nature is the prelude to grace.” (Exposition of the De Trinitate, 2, 3.)

Theology (ceiling tondo), by Raffaello Sanzio.
Fresco, 1509-11; Stanza della Segnatura,
Palazzi Pontifici, Vatican.