Evodius: Tell me, please, whether God is not the cause of evil.
Of course, as St. Augustine points out, this question is silly for the Christian.
But if you know or believe that God is good (and it is not right to believe otherwise), God does not do evil. Also, if we admit that God is just (and it is sacrilege to deny this), He assigns rewards to the righteous and punishments to the wicked—punishments that are indeed evil for those who suffer them. Therefore, if no one suffers punishment unjustly (this too we must believe, since we believe that the universe is governed by divine Providence), God is the cause of the second kind of evil, but not of the first.
It’s not that God causes or does evil in an absolute sense; that would be heretical (as he says in the first sentence) because God is good. There is a relative sense in which he might be said to do “evil,” though, if we are talking about the punishment of the wicked, says our author: the evil man considers punishment to be an evil thing that happens to him. In point of fact, though, Augustine reminds us that God’s justice demands that he punish the wicked and reward the righteous.
Would it be just if God punished the wicked but did not reward the righteous? It seems not, in Augustine’s view. The complaint that might be offered: “You punish them for doing evil, but you do not reward us for doing well.” Some might pretend that no one does good, but the Bible (Mt. 25:31-46) does not seem to bear them out.
Now the book is on free will, and so of course we ought to expect St. Augustine to address its relation to justice.
[E]ach evil man is the cause of his own evildoing. If you doubt this, then listen to what we said above: evil deeds are punished by the justice of God. It would not be just to punish evil deeds if they were not done willfully. [Emphasis added]
God’s justice demands that he punishes evil deeds, but if we are compelled to do them, it simply cannot be said that we are liable for them.
[Quotations above taken from Book I of On Free Choice of the Will, p. 3]
We see the same thing in Book II, chapter I:
Both punishment and reward would be unjust if man did not have free will. [p. 36]
The fact that God foreknows that we will sin does not mean that we lack free will. St. Augustine offers additional arguments about this in the book, but for our purposes here it is sufficient to remark that what we’ve said above applies here as well. If God’s foreknowledge constitutes a compulsion whereby our free will is removed, he could not justly punish the wicked for sin nor reward the righteous for good.
[L]et us acknowledge both that it is proper to His foreknowledge that nothing should escape His notice and that it is proper to His justice that a sin, since it is committed voluntarily, should not go unpunished by His judgment, just as it was not forced to be committed by His foreknowledge.
[Book III, chapter IV; p. 95]
It might be worth pointing out what we’ve seen repeatedly already (and what we see again above) concerning St. Augustine’s views on the reward that awaits the righteous: in short, there is one. He constantly refers to it as a reward for good deeds done. Although he doesn’t use the word in what we’ve seen above, he steadfastly recognizes this reward as something that one merits by his deeds.