Theatine priest and reformer. Born of a wealthy family at Castronuovo (Potenza) in the kingdom of Naples, he studied civil and canon law, was ordained priest and became a prominent advocate in the Church courts. He was ambitious as well as devout, but experienced a conversion c.1552 which resulted in his total commitment to the cure of souls and to religious education. He was commissioned to reform a decadent nunnery in 1556, where he met violent resistance, but eventually imposed strict enclosure and other monastic reforms. In the same year he joined the Theatine congregation (founded by Cajetan) and spent the next fourteen years in their Naples house, becoming in turn novice-master and superior. In 1570 he moved to Milan to found houses there and at Piacenza at the invitation of Charles Borromeo. Throughout his working life he propagated the decrees of the Council of Trent.
In 1582 he returned to Naples, where he remained for the rest of his life. Not outstanding as organizer or administrator, he excelled as preacher and writer for converting sinners and refuting heresies. Personal charity included forgiveness for the murderer of his nephew and the willingness to take him into his household. He died of apoplexy just before saying Mass, a scene depicted by contemporary painters. Even in lifetime miracles were attributed to him, while after death some of his hair was removed as relics. The blood consequently flowed, as it did when physicians made incisions, and subsequently liquefied like that of Januarius. The canonization commission rejected the claim that this was miraculous, but judged Andrew worthy to be declared a saint. He was accordingly canonized in 1712. Feast: 10 November.
AA.SS. Nov. IV (1925), 609–23; devotional writings published at Naples in 1733–4, for which see B. Bas, ‘Bibliografia di S. Andrea Avellino’, Regnum Dei, xiv (1958), 303–61;A. Lechat, ‘La conversion de S. André Avellin’, Anal. Boll., xli (1923), 139–48;B.L.S., xi. 81–2;Bibl. SS., i. 1189–90.