Alphonsus Liguori CSsR (1696–1787), sometimes called Alphonsus Maria de Liguori or Saint Alphonsus Liguori, was an Italian Catholic bishop, spiritual writer, composer, musician, artist, poet, lawyer, scholastic philosopher, and theologian.
He founded the Congregation of the Most Holy Redeemer, known as the Redemptorists, in November 1732. In 1762 he was appointed Bishop of Sant'Agata dei Goti. A prolific writer, he published nine editions of his Moral Theology in his lifetime, in addition to other devotional and ascetic works and letters. Among his best known works are The Glories of Mary and The Way of the Cross, the latter still used in parishes during Lenten devotions.
He was canonized in 1839 by Pope Gregory XVI and proclaimed a Doctor of the Church by Pope Pius IX in 1871. One of the most widely read Catholic authors, he is the patron saint of confessors.