At first was a soldier and a veteran of war, who turned to God, and embraced the Christian faith when he was miraculously freed from imprisonment. He devoted the whole of his life to the care of orphans, the education of children, and the assistance of the sick.

He founded the Order of Clerks Regular called the Somaschi for the purpose of helping orphans, children, and the poor. Jerome died at Somaschi near Bergamo in 1537, at the age of 51.