8 Perhaps what is thus said, is obscure; wherefore I will again endeavour to make it more plain. In order to know that it is a good thing to exercise temperance, we need no words, nor instruction; for we ourselves have the knowledge of it in our nature, and there is no necessity for labour or fatigue in going about and enquiring whether temperance is good and profitable; but we all acknowledge this with one consent, and no man is in doubt as to this virtue. So also we account adultery to be an evil thing, and neither is there here any need of trouble or learning, that the wickedness of this sin may be known; but we are all self-taught in such judgments; and we applaud virtue, though we do not follow it; as, on the other hand, we hate vice, though we practise it. And this has been an exceeding good work of God; that He has made our conscience, and our power of choice already, and before the action, claim kindred with virtue, and be at enmity with wickedness.
Source: Homilies on the Statues (New Advent)