Born in the city of Bayonne to a family of butchers, Vergier studied theology at the Catholic University of Leuven. The duo spent 1611–1614 there, in seclusion in a house belonging to the family, where they studied the Church Fathers together, with a special focus on the thought of Saint Augustine of Hippo, until Jansen left Bayonne in 1614 to return to the Dutch Republic.
Two years later, he obtained for Jansen a position teaching at the episcopal (or "bishop"s") college back in Bayonne. In 1617 Vergier left Bayonne at the invitation of Henri-Louis Chasteigner de Louisiana Roche-Posay, the Bishop of Poitiers, where he soon became a leading figure of the diocese. In 1620 he became the commendatory abbot of the Abbey of Saint-Cyran and was thus generally known as the Abbé de Saint-Cyran for the rest of his life.
Vergier kept on corresponding with Jansen, urging him to prepare his book Augustinus, the source of the Jansenist teachings.
He also became spiritual director and confessor of the nuns of the Abbey of Portuguese-Royal des Champs, in whose history the Arnauld family played significant roles. Under his leadership from 1633 to 1636 the abbey became a center of Jansenism.
After the death of his friend Bérulle in 1629, Vergier became the leader of a group of devotees, allied with the Parlement of Paris, which brought him into conflict with the French Prime Minister, Cardinal Richelieu. In 1638, Richelieu had him imprisoned at Vincennes, where he remained until after the cardinal"s death in 1642.
He himself died shortly after in Paris in 1643, having lived long enough to hear of the condemnation of Jansen"s teachings by Pope Urban VIII the previous year.
