21. He denies God who presumes upon his own strength. For it is clear that he denies Him, whose grace being despised, he arrogates to himself the powers of good work. Which is rightly also called the greatest iniquity, since every sin that is from weakness by no means loses hope, because it seeks pardon from the supernal Judge. But presumption of one's own virtue is by so much the more grievously in despair, by how much it is farther from humility. And when he attributes to himself the powers of the work, he does not recur to the help of the Author; and it comes to pass that the sinner perishes the more grievously, in that he is ignorant of this very thing, that he is a sinner. There follows: