Anti-pelagian Writings by St. Augustine
(4.) The Fourth Breviate.
IV. |We must ask, again,| he says, |What is sin, -- an act, or a thing? If it is a thing, it must have an author; and if it be said to have an author, then another besides God will seem to be introduced as the author of a thing. But if it is impious to say this, we are driven to confess that every sin is an act, not a thing. If therefore it is an act, for this very reason, because it is an act, it can be avoided.| Our reply is, that sin no doubt is called an act, and is such, not a thing. But likewise in the body, lameness for the same reason is an act, not a thing, since it is the foot itself, or the body, or the man who walks lame because of an injured foot, that is the thing; but still the man cannot avoid the lameness, unless his foot be cured. The same change may take place in the inward man, but it is by God's grace, through our Lord Jesus Christ. The defect itself which causes the lameness of the man is neither the foot, nor the body, nor the man, nor indeed the lameness itself; for there is of course no lameness when there is no walking, although there is nevertheless the defect which causes the lameness whenever there is an attempt to walk. Let him therefore ask, what name must be given to this defect, -- would he have it called a thing, or an act, or rather a bad property in the thing, by which the deformed act comes into existence? So in the inward man the soul is the thing, theft is an act, and avarice is the defect, that is, the property by which the soul is evil, even when it does nothing in gratification of its avarice, even when it hears the prohibition, |Thou shalt not covet,| and censures itself, and yet remains avaricious. By faith, however, it receives renovation; in other words, it is healed day by day, -- yet only by God's grace through our Lord Jesus Christ.