Alphonsus Liguori, born in 1696, was the son of an ancient Neapolitan family. His father was an officer in the Royal Navy. At the age of sixteen, Alphonsus received his doctorate in both canon and civil law and for nearly ten years practiced at the bar. When he found that one of the legal cases he was defending was not based on justice but on political intrigue, he gave up the practice of law and dedicated his life to God.

Ordained to the priesthood in 1726, St. Alphonsus Liguori joined a group of secular priests dedicated to missionary activities. He involved himself in many kinds of pastoral activities, giving missions and organizing workers, and had a part in the founding of an order of contemplative nuns.

In 1732, he founded the Redemptorists, a congregation of priests and brothers, to work especially among the country people of Italy who often lacked the opportunity for missions, religious instruction, and spiritual retreats. Strangely, his first companions deserted him; but Alphonsus stood firm, and soon vocations multiplied and the congregation grew.

The Redemptorists were approved by Pope Benedict XIV in 1749, and Alphonsus was elected superior general. In 1762, he was appointed bishop of Sant' Agata dei God and as bishop he corrected abuses, restored churches, reformed seminaries, and promoted missions throughout his diocese. During the famine of 1763-64, his charity and generosity were boundless, and he also carried on a huge campaign of religious writing.

In 1768, he was stricken with a painful illness and resigned his bishopric. During the last years of his life, problems in his congregation caused him much sorrow and when he died on August 1, 1787, at Pagani, near Salerno, the Redemptorists were a divided society. He was beatified in 1816, canonized in 1839, and declared a Doctor of the Church in 1871.