Theologian; b. Paris, c. 1598; d. Pont-de-Salars, near Rodez, Sept. 15, 1668. Early in his career Habert tried to carry on the literary tradition of his family by publishing several books of poetry. In 1623 he became a fellow of the Sorbonne, licenciate and doctor in 1626.
About 1639 it was rumored that Cardinal A. J. richelieu was planning to set up a French patriarchate to achieve greater independence from Rome. Against the Oratorian Charles Hersent, who publicized this idea under the pseudonym of Optatus Gallus, Habert launched his De consensu hierarchiae et monarchiae adversus paraeneticum Optati Galli schismatum fictoris libri VI (Paris 1640). Noteworthy is his Latin version of the Greek pontifical entitled 'ΑρχιερατκόνLiber Pontificalis Ecclesiae graecae (Paris 1643).
After 1626 he was canon theologian of Notre Dame Cathedral and preacher at the royal court. In 1642–43, on Richelieu's orders, he vigorously opposed Cornelius jansen's augustinus in three sermons at the cathedral. In these he compared the book's doctrine with that of Calvin. A. Arnauld attacked these sermons in an apologetic diatribe; Habert responded in his La défense de la foy de l'Église et de l'ancienne doctrine de Sorbonne (Paris 1644). Against an expression in the preface of Arnauld's Fréquente Communion presenting Peter and Paul as the "two-fold heads of the Roman Church," Habert issued his De cathedra seu primatu singulari S. Petri (Paris 1645).
He was named bishop of Vabres in April 1645. The following year at Paris he published against Jansenists and Augustinians his most significant dogmatic work, Theologiae graecorum patrum vindicatae circa universam materiam gratiae libri III, an exposition of the Greek Fathers' doctrine of grace.
Bibliography: f. x. bantle, Lexikon für Theologie und Kirche, ed. j. hofer and k. rahner (Freiberg 1957–65) 4:1297. j. orcibal, "Le patriarcat de Richelieu," in Jean Duvergier de Hauranne, abbé de Saint-Cyran, Appendices (Paris 1948), 108–132. l. ceyssens, "L'anijanséniste Isaac Habert," Bulletin de l'Institut historique belge de Rome [=Jansenistica minora XI] 42 (1972), 237–305
[c. r. meyer/
j. m. gres-gayer]