Last week I spoke to the youth about the influence of Augustine. In his book, The Consequences of Ideas, R.C. Sproul includes Augustine in his list of influential thinkers. Below is a segment from his book.

THE PROBLEM OF EVIL

Wrestling with the problem of evil, Augustine sought to define evil in purely negative terms. Evil is a lack, privation, negation of the good. Only that which was first good can become evil. Evil is defined against the backdrop of the prior concept of the good. Evil depends on the good for its very definition. We speak of evil in terms of unrighteousness, injustice, and lawlessness. The Antichrist depends on Christ for his very identity. As a parasite depends on its host for its existence, so evil depends on the good for its existence. Anything that participates in being, so far that it exists, is good. Nonexistence is evil. If anything were purely or totally evil, it could not exist. Evil is not a substance or a thing. It is a lack or privation of the good.

At this level Augustine seems to be defining evil in purely ontological terms. If this were the case, Augustine would have to say that evil is a necessary consequence of finitude. God cannot create an ontologically "perfect" being. To do so would be to create another God. Even God cannot create another God, because the second God would be, by definition a creature.

To avoid the ontological necessity of evil, Augustine turned to free will. God created man with a free will, in which he also enjoyed perfect liberty. Man had the ability of choosing what he wanted. He had the ability to sin and the ability not to sin. He freely chose to sin out of his concupiscence (an inclination that leans to sin but is not sin).

As a result of the first sin, man lost his liberty but not his free will. He was plunged, as a divine punishment, into a corrupt state known as original sin, losing the ability to incline himself to things of God. This resulted in man's absolute dependence on a work of divine grace in his soul if he were ever to move toward God. Fallen man is in bondage to sin. He still has the faculty of choosing, a will free from coercion, but he now is free only to sin, because his desires are inclined only toward sin and away from God. Now posse non peccare, "the ability not to sin," is lost and in its place is non posse non peccare, "the inability not to sin." With this view Augustine combated the heretic Pelagius, who denied original sin. Pelagius argued that Adam's sin affected Adam alone and that all people have the ability to live perfect lives.

Sproul, R.C. Augustine: Doctor of Grace. The Consequences of Ideas. Wheaton: Crossway Books. 2000. 62-63