As Erasmus sees it, it is essential that man should have freedom of choice. Without it there would be no sense in meting out praise or blame, since there could be no possibility of man’s meriting either. Nor would there be any sense in God’s law and commandments, for their imperative “Thou shalt” implies the indicative “Thou canst,” and to deny the latter is to stultify the former. In practice, moreover, to teach men that they have no real choice can only foster irresponsibility and encourage antinomianism. But that is not the worst of it. If man acts solely from necessity, having no freedom, he cannot possibly deserve either reward or punishment; hence if God rewards and punishes men he is manifestly unjust. Erasmus’ concern for human freedom is thus also a concern for the character of God. Not that he is at all unmindful of God’s grace, which transcends any strict legality, and without which no man can possibly be saved. Yet men must have the freedom to choose or refuse grace, so that if they are damned for the lack of it, their damnation will at least have been justly deserved. At this Luther wryly observes that people seem more upset by the injustice of God’s wrath in damning the undeserving than by the injustice of his grace in saving the undeserving!
The Bondage of the Will
Luther’s Works Vol. 33