d. c. 445 · 5th c. · 1 work
Saint Vincent of Lérins was a fifth-century monk and priest of the island monastery of Lérins, off the coast of Gaul near present-day Cannes. A Latin ecclesiastical writer of the generation after the Council of Ephesus, he is remembered above all for furnishing the Church with a rule for discerning authentic Christian doctrine.
Little is known of his life with certainty. The early sources report only that, after a period in secular affairs, he withdrew from the world and entered the monastery of Lérins, where he was ordained priest and devoted himself to study, writing under the pen-name Peregrinus (“the pilgrim”).
His enduring work is the Commonitory (c. 434), which formulates the famous test of catholicity — that authentic faith is what has been believed “everywhere, always, and by all” (quod ubique, quod semper, quod ab omnibus) — and reflects on how the Church's understanding of doctrine may legitimately grow while remaining the same in substance.
He is reported to have died about 445 and is venerated as a saint, his relics kept at Lérins; his commemoration is observed on 24 May. Because the surviving record is so sparse, much of what is known of him is drawn from his own writing.
Sources: Orthodox Church in America — Saint Vincent of Lérins · Encyclopædia Britannica — St. Vincent of Lérins