from 405 to condemnation at the Council of Ephesus (431); key rulings 411–418

The Pelagian controversy

The British monk Pelagius encountered Augustine's theology in Rome (from 405); their dispute concerned original sin, free will and grace. Pelagius's disciple Celestius was condemned at Carthage (412). Pelagius himself was temporarily cleared at the synods of Jerusalem and Diospolis (414–416), but was then condemned at the synods of Mileve and Carthage (416) and by decree of Pope Zosimus (418).

The Council of Carthage of 1 May 418 adopted eight canons against Pelagianism, and the Third Ecumenical Council at Ephesus (431) anathematized Pelagianism. Augustine's strict doctrine of predestination met resistance in southern Gaul (semi-Pelagianism), and the ruling of 418 remained the Church's last official pronouncement on justification until the Reformation.