Monti was born in Como. He studied for the Catholic priesthood at the Villoresi di Monza seminary. He was ordained as a priest in 1879. The Bishop of Como encouraged Monti to study theology in Rome. Monti received his degree in theology in 1880. His first job as a priest was in Urio, a small town in Province of Como. Then he was a priest at the church of San Giorgio in Como until 1881. After 1881 he was the chaplain of the church's cemetery.