Saint Anthony Maria Zaccaria (1502 – 1539) was the originator of the Forty Hours devotion to the Blessed Sacrament.
Born in Cremona, Italy in 1502 to noble parents, his father died when he was two his father died. He took a private vow of chastity at an early age.
The saint studied philosophy at the University of Pavia, and, from 1520, medicine at the University of Padua. After completing studies in 1524, he practised as a doctor in Cremona for three years. In 1527, he started studying for the priesthood and was ordained in 1528.
Initially he worked mainly working in hospitals and institutions for the poor. He subsequently established three religious orders, initially in Milan: the Clerics Regular of St Paul, commonly known as the Barnabites; a female branch of uncloistered nuns, the Angelic Sisters of St. Paul; and a lay congregation for married people, the Laity of St. Paul (Oblates of St. Paul). Their aim was the reform of the decadent society of their day, beginning with the clergy and religious.
While on a mission to Guastalla, Italy, in 1539, he caught a fever. Combined with the strict penances he performed, his health waned and he died on 5 July 1539, at the age of 37.