Girolamo Zanchi (Latin "Hieronymus Zanchius," thus Anglicized to "Jerome Zanchi/Zanchius"; February 2, 1516 – November 19, 1590) was an Italian Protestant Reformation clergyman and educator who influenced the development of Reformed theology during the years following John Calvin's death.
He was born the son of a noble lawyer and historian, in Alzano Lombardo near Bergamo. His father died in the plague of 1528 and his mother died only three years later. At age 15 he entered the monastery of the Augustinian Order of Regular Canons, where he studied Aristotle, languages and divinity. After completing his studies, he went to Lucca, and there under the influence of Peter Martyr Vermigli he opted for a theological career, being especially impressed by Vermigli's lectures on Romans. In addition to works of the Fathers, he became aware of Martin Bucer and Philipp Melanchthon, also read Martin Luther's writings and the Swiss reformers. John Calvin, however, had the greatest influence on him.
Even after Vermigli’s forced flight in 1542, Zanchi remained as a teacher of Greek at the monastery school. In 1551, however, he also was forced into exile. After a brief stay in Geneva, he wanted to go to England, but was called to Strasbourg and worked there as a professor of the Old Testament at the college of St. Thomas. His style is legalistic, and he interpreted with meticulous accuracy. In his overall theological orientation, he has been described as "a Calvinist in terms of theological content, and a Thomist in terms of philosophy and methodology." He was one of the most learned theologians of the second half of the 16th Century, if he is not considered to be an especially original thinker. He was regarded an excellent teacher.