At sixteen he took the religious habit at San Domenico in Fiesole, where he studied under the direction of Savonarola and other eminent professors.
His genius, industry and erudition won him influential friends, among them the Cardinals de'Medici, subsequently popes Leo X and Clement VII.
Here he was instrumental in establishing a hospital for the plague-stricken, and by his zeal and eloquence, diverted an irruption of Waldensianism and Lutheranism from the city, receiving in acknowledgement the much coveted rights and privileges of citizenship.
Here he also was in contact with the polymath and Hebraist Michael Servetus, whom he gave his notes to, and designated him as his heir to the scholarly study of the bible after he would have died.
The merit of his Veteris et Novi Testamenti nova translatio (Lyon, 1527) is said to lie in its literal adherence to the Hebrew, which won for it the preference of contemporary rabbis and induced Leo X to assume the expenses of publication until his death.