Summa summae S. Thomae, Tomus III

I answer. Affirmative.

Proof. Divine revelation must be judged possible if it involves no repugnance, whether on the part of God revealing, on the part of man receiving the revelation, or on the part of the things revealed. But on no side is there any repugnance. Therefore.

Proof. The first part of the minor. Since God is infinitely wise and powerful, it belongs to him to judge whether it is opportune, indeed necessary, that he manifest to his creatures truths hidden by their very nature; he has countlessly many ways ready at hand by which he may make known the things that concern him, or his wills. Nor will anyone deny this, unless he be an atheist, that is, a madman, nor even will he call it into doubt. For if any man could lay open all his thoughts to another man, why would this be impossible for God?

Proof. The second part. Man received intelligence and reason from God for no other purpose than to perceive truth, of which God himself is the one and essential source. Nothing therefore on his part stands in the way of his receiving any truths whatsoever proposed by God, just as men are accustomed to communicate whatever things to one another.

Proof. The third part. If certain truths contribute to a more perfect knowledge of God and to his greater glory, as also to the benefit of men, nothing prevents them from becoming the object of divine manifestation, as is evident.

These points are confirmed by the common sense of mankind, which has never detected any repugnance in revelations of this kind; indeed it has judged them necessary, as is clear from the history of all peoples, which have accepted revelations, whether true or fictitious. Therefore.

You will object. It ill beseems the divine majesty to stoop so far as to address wretched creatures. Therefore.

I answer. It did not ill beseem God to create man, and indeed so as to lead him to happiness. Much less, therefore, does it ill beseem him to point out to man the safe way to his end, which man could never find by himself; this is most consonant with the divine wisdom and goodness.