Pelagius

A preacher, Pelagius found himself in Rome, and became concerned about the moral laxity of society he saw there. He blamed this laxity on the theology of divine grace preached by St Augustine of Hippo, among others. He taught a doctrine which has come to be called Pelagianism, holding that humans are responsible themselves for their own moral improvement, and God's grace can only assist men in doing those good deeds that remain within human ability.

When Alaric sacked Rome in 410, Pelagius fled to Carthage, where he came into further conflict with Augustine. His follower Coelestius was condemned by a church council there. Pelagius then fled to Jerusalem, but Augustine's followers were soon on his trail; Orosius went to Jerusalem to warn St Jerome against him.

Pelagius's teachings about sin and atonement were condemned as heresy at the Council of Carthage[?] in 417.