Born in the late fourth century in Toulouse in Gaul, Saint Vincent initially served in the military, but later left the world to become a monk at the renowned Lérins Monastery, where he was ordained to the priesthood. He is widely known for his work, Commonitorium, which he wrote around the year 434 AD, in which he differentiated between the Church's teachings and the heresies of his time. He is remembered for writing that Christians must follow the true faith that has been held “everywhere, always, and by all.” He also defended the term “Theotokos” with regard to the Mother of God in opposition to the teachings of Nestorius that were condemned at the Third Ecumenical Council.
Saint Vincent died peacefully in 456 AD. His relics are preserved at Lérins.