St. Augustine
When Catholics discuss saints who were once great sinners, the first one that comes to mind is St. Augustine of Hippo and for good reason: as a teenager Augustine abandoned the Catholic faith in which he had been raised by his mother, St. Monica, moved in with a mistress, and together they had a son out of wedlock. Augustine became a well-known orator and studied the pagan philosophies of Plato. Augustine became a Christian at age 32, after having discussions about Christianity with a friend, and hearing a child’s voice telling him to pick up a scroll and read it. This conversion story is one of the most famous. After being baptized in 387, Augustine moved back to his hometown of Tagaste, in North Africa, to found a monastic community and became a monk. In 391, the church at nearby Hippo pressed him to become a priest and five years later, he was made Bishop of Hippo. As a church leader, he became an active pastor, not only for his congregation and diocese, but for his faith.