Pelagius

Pelagius ( pə-LAY-jee-əs; fl. c. 354–418) was a Christian theologian known as an ascetic monk and promoting a system of doctrines (termed Pelagianism by the Catholic Church) which emphasized human choice in salvation and denied original sin. Pelagius was acquitted of heresy at the Synod of Diospolis in 415 but his doctrines were harshly criticized by Augustine of Hippo, especially the Pelagian views about mankind's good nature and individual responsibility for choosing asceticism. Pelagius especially stressed the freedom of human will. Very little is known about the personal life and career of Pelagius, although he was thought to be of British-Celtic or possibly Romano-British origin and fluent in Latin before arriving in Rome and later North Africa.

Notable works: Verba seniorum

Source: Wikipedia — https://en.wikipedia.org/wiki/Pelagius