michel DE Bay) (1513-1589. Flemish Catholic theologian. Augustinian in outlook, forerunner of and an influence on Cornelius Jansen and Jansenism,* he had been educated at Louvain and taught philosophy (1544) and later theology there. In his thirties he turned to serious study of Augustine, and developed a radical Augustinian position which denied many of the doctrinal positions developed by medieval Scholasticism.* Attacking the idea of merit in good works, the immaculate conception, papal infallibility, the limited effect of the fall, any conditions on predestination, and similar views, his teachings soon aroused violent controversy. To his opponents, especially the Jesuits, they seemed close to Calvinism. By 1560 the theologians at the Sorbonne denounced his version of Augustinianism, and theological faculties at the Spanish universities followed suit. A trip by Baius and his colleague John Hessels to the * to defend their views proved abortive, and in 1567 Pius V issued a condemnation of several propositions Baius was alleged to have taught. Denying that he had in fact done so, he continued to present his Augustinianism as before. Controversy continued, and in 1579 issued a further and more specific condemnation, to which Baius submitted, though still claiming he was misunderstood. His teachings were surely contrary to the dominant understanding of the post-Trent church. The controversy did not end with Baius's death, but broke out again and more importantly with the Jansenist movement a short time later.
N.J. Abercrombie, The Origins of Jansenism (1936); H.J.D. Denzinger, Enchiridon symbolorum (tr. R.J. Deferrari as The Sources of Catholic Dogma, 1957); M.J.P. Van Doozen, Michael Baius, zijn leer over de mens (1958).