MAINARDI, AGOSTINO. - An Augustinian who adhered to the "Reformation" and later became a pastor in Chiavenna, in the Grisons, in 1548 at Caraglio (Cuneo) and died in Chiavenna on 31 July 1563. It is not known precisely when he began to incline toward Protestantism. His Lenten sermon of 1532 in Asti and especially that of 1538 in Rome, in S. Agostino—where he provoked the protests of St. Ignatius of Loyola and the Jesuits—made him suspect. Finally, in Milan in 1541, during the Lenten sermon in the church of S. Marco, Mainardi advanced ideas so openly heretical that the governor, the Marquis del Vasto, reported him to the captain of justice and the podestàs of the duchy for arrest.
Soon after (probably in the summer of 1541), as his position became untenable, Mainardi took flight. He preached in Tirano and then proceeded to the Grisons, where he became pastor of the Reformed community in Chiavenna. BULLINGER, HEINRICH (v.), whose ideas he supported, he soon came into conflict with groups of Anabaptists, especially Italian exiles, who were numerous in the area. Among these "skeptical academics" eager for "strange and novel things," as the Protestants called them, Camillo Renato (v.) in particular opposed Mainardi. The controversy with Renato concerned the question of the Lord’s Supper, which Mainardi understood in a Calvinist sense, while Renato and his followers regarded it as devoid of value. The dispute, which began around 1545, continued until 1551, Renato having been excommunicated in 1550 and then banished from the Rhaetian Churches; but it continued in a latent form and was later resumed when Renato’s ideas were spread and developed against Mainardi by Pietro Leoni and Ludovico Fieri. On this occasion, too, after the Anabaptists were tried, Mainardi emerged victorious.
Among Mainardi’s works are the *Trattato dell'Eucaristia* (1552), the *Trattato dell'unica e perfetta satisfazione di Cristo* (1561), and *Un pio et utile sermon della Gratia di Dio* (1562). The book *Anatomia della Messa*, published under the pseudonym Antonio di Adamo, an obscene parody of the divine Sacrifice, is apparently his; it was translated into French by Calvin’s secretary, Villars, and into Latin by P. P. Vergerio.