Church historians have often observed that there is no such thing as a completely new heresy. Their point is that the errors the church faces today are simply repackaged versions of heresies the church dealt with hundreds of years ago. And one of the most frequently recurring heresies is the one most closely associated with Pelagius.
Pelagius was a British monk who lived circa AD 354–420. He was a man zealous for good works and who was very concerned about what he perceived as moral laxity in the church of his day. In his theology, Pelagius stressed human ability, believing that if God commands people to do something, they must have the ability to do it without His assistance. After all, he reasoned, it would be unjust to command people to do something they were unable to do, and since the Lord is just, His commands necessarily imply human ability.
Thus, Pelagius reacted strongly against the teaching of Augustine of Hippo, particularly Augustine’s prayer, “Grant what You command and command what You desire.” Because of his view of human ability, Pelagius could not abide Augustine’s asking the Lord to give him the ability and willingness to obey God’s law.To ask for such enabling would mean that we are unable to do what is good in the Lord’s eyes without the Lord’s assistance.
Augustine prayed his prayer because he had a far greater respect for the power of sin than Pelagius did. Pelagius failed to reckon with the fall and original sin. Adam’s failure, Paul tells us, results in all of his natural descendants being born as sinners. We are guilty as soon as we are conceived, for we are born in Adam and the guilt of his sin is imputed to us—those whom he represented before God in Eden. With guilt, we receive a corrupted nature that is incapable of pleasing God (Rom. 5:12–21). “In Adam all die” (1 Cor. 15:22), and dead men can do nothing unless God brings them to new life. This means that in light of our post-fall condition, Pelagius was wrong to suggest that God’s commands imply human ability to keep them. In Adam, we chose to surrender our ability to obey, but God did not stop being the Lawgiver. He justly commands sinners to do what they, because they willingly surrendered their ability to please Him, cannot do.
Augustine asserted that divine grace is absolutely necessary for salvation. Because we are born slaves to sin, God must act to free us, or we will be slaves to evil forever.