Saint Antonio Maria Zaccaria (born 1502, Cremona, duchy of Milan—died July 5, 1539, Cremona; canonized May 27, 1897; feast day July 5) was an Italian priest, physician, and founder of the congregation of Clerks Regular of St. Paul, or Barnabites, a religious order devoted to the study of the Pauline Letters.
Receiving his doctorate in medicine from the University of Padua in 1524, he practiced at Cremona for three years. He then studied theology and was ordained in 1528, later being transferred to Milan, where, under the influence of his confessor, he organized (1530) the Barnabites.
Zaccaria’s congregation preached and administered charitable work among the Milanese and was approved by Pope Clement VII in 1533. Zaccaria later founded the Angelicals of St. Paul, a similar order for women, which Pope Paul III approved in 1535. The two congregations performed missionary and educational work in Milan and elsewhere, using the teachings of the Apostle St. Paul as their guide.
Toward the end of his life Zaccaria secured for his order’s headquarters the ancient Milanese church of St. Barnabas, from which their popular name derives. There are Barnabite monasteries in Italy, Austria, Belgium, Spain, and South America.