Zanchi, Jerome a clergyman and theologian of the German Reformed Church, was born at Alzano, in the territory of Bergamo, February 2, 1516, and was the son of the historian Zanchi. He entered the Augustilian order of regular canons in 1531, engaged in philosoplical and theological studies, and, on their completion, came with his friend, count Celso Martinengo of Brescia, to the monastery of Lucca, where Vermigli was teaching, and where they became acquainted with the writings of Luther, Melanchthon, Bullitnger, and Calvin. They soon afterwards came into notice as evangelical preachers, and were compelled to flee — Martinengo to Milan and Geneva, where he became pastor of the Italian Church, in 1552, and Zanchi to Switzerland and Geneva, in 1551. In 1553 Zanchi accepted a professorship of the Old Test. at Strasburg, where Marbach and other Lutherans were his colleagues, the association involving him in controversies upon the doctrines of the antichrist, predestination, and the perseverance of the saints, which began in 1561, and were superficially settled by arbitrators, who drew up a formal agreement, which was signed by all the clergy and professors of the city, Zanchi, however, appending a reservation to his signature intended to prevent his being compelled to teach what he did not receive as the truth. Calvin and other reformed theologians, however, censured the yielding temper which Zanchi had exhibited, and thus induced him to speak his sentiments more positively. This naturally renewed the strife and involved disagreeable consequences, from which he was glad to escape by accepting a call to Chiavenna as pastor of the Italian congregation. He had previously declined repeated calls to a similar post at Lysons., False teachers and uneasy Italian agitators troubled him at Chiavenna, and in 1564 a pestilence interrupted the services of his Church and compelled his retirement to a mountain near Piuri, where he occupied himself with writing a sketch of his controversy with Marbach, which afterwards appeared under the title of Miscellanaea (1566, 4to). In 1568 he became professor of theology at Heidelberg, and rapidly earned the first place among the scholars of the theological faculty. His advice was sought by persons in every quarter and upon all the debated questions of the day, e.g., the sacraments, the Trinity, the mediation of Christ, and replies in great number were written to inquirers, sometimes in the name of the faculty, and often in his own name, all tending to the confirmation of the teachings of Reformed orthodoxy. He was equally zealous and influential in the work of introducing a strict discipline in the churches of the palatinate. Of larger theological works written by him in this period we mention De Tribus Elohim, etc. (1572), which is chiefly important as collocating the grounds upon which the antitrinitarians based their opinions; De Natum Dei, etc.; a sort of speculative philosophy of religion, in which the doctrine of predestination especially is carried to its logical consequences; and De Operibus Dei inftra Spatium Sex Dierum Creatis, a cosmology in which dogmatic hypotheses and physical facts are intermingled-interesting as showing the amount of knowledge possessed, or supposed to be possessed, respecting nature and natural forces in that day. A fourth work, De Primi Hominis Lapsu, etc., was begun at Heidelberg, but not completed. A Lutheran prince succeeded to the throne of the Palatinate, and Zanchi was dismissed. The newly established University of Neutstadt-on-the-Hardt .received him, and made him its professor of the New Test. in 1578, and this post he retained until he died, November 19, 1590, though he had been invited to return to Heidelberg when the Palatinate was restored to Calvinism. In 1577 he was required to write a confession by the deputies of the Reformed churches, then assembled at Frankfort, which confession was intended to be opposed to the Formula of Concord. This work became the basis of the Harmonia Conf. Fidei Orthodoxarum of Beza and Danaeus (1581). His children collected his works and published them after his dea, th, though no complete edition appeared prior to that of Geneva (1619, 3 volumes, fol. 8 parts). These works rank among the leading sources of the Rleformed theology of his time, but are already tainted with the scholastic spirit. See Schmid, in Stud. u. Krit. 1859; Herzog, Real-Encyklop. s.v.