Pelagius the Theologian (Πελάγιος ὁ Θεολόγος)
Life Pelagius was a Christian theologian active in the late 4th and early 5th centuries CE, likely of British origin. A well-educated moral reformer in Rome, he taught that rigorous human effort and free will could achieve a sinless life, directly opposing Augustine of Hippo’s views on grace [1][2]. After fleeing Rome in 410 CE, his doctrines were condemned as heretical at the Council of Carthage in 418 CE, leading to his excommunication [1][2].
Works Though authorship is often disputed, major works attributed to him include the fragmentary treatise De libero arbitrio (On Free Will), his Libellus fidei ad Innocentium (Confession of Faith to Pope Innocent), the exegetical Expositiones xiii epistularum Pauli (Commentaries on the Thirteen Epistles of Paul), and the hortatory Letter to Demetrias [1][3]. Many survive only in fragments preserved by his opponents [1][3].
Significance Pelagius is the namesake of the Pelagian controversy. Augustine’s forceful refutation of his teachings on human nature and free will profoundly shaped subsequent Western Christian doctrine on grace, original sin, and predestination [1][2].
Sources 1. Stanford Encyclopedia of Philosophy (Pelagius): https://plato.stanford.edu/entries/pelagius/ 2. Internet Encyclopedia of Philosophy (Pelagius): https://iep.utm.edu/pelagius/ 3. Perseus Digital Library (Pelagius): https://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0104:entry=pelagius-bio-1
Available Works
Sources
- Stanford Encyclopedia Entry (Stanford Encyclopedia of Philosophy) Accessed: 2026-01-26
- IEP Entry (Internet Encyclopedia of Philosophy) Accessed: 2026-01-26
- Perseus Entry (Perseus Digital Library) Accessed: 2026-01-26