City of God – For if two men, alike in physical and moral constitution, see the same corporal beauty, and one of them is excited by the sight to desire an illicit enjoyment while the other steadfastly maintains a modest restraint of his will, what do we suppose brings it about, that there is an evil will in the one and not in the other? What produces it in the man in whom it exists? Not the bodily beauty, for that was presented equally to the gaze of both, and yet did not produce in both an evil will.