He was ordained priest at the age of twenty-seven, and for some time fulfilled the duties of chaplain in a hospital. In 1705, when he was thirty-two, he found his true vocation, and thereafter devoted himself to preaching to the people.

God will decide the time you discover your vocation.

Penance

http://abbey-roads.blogspot.com/2010/04/penance-penance-penance.html

The call to penance began with the ministry of John the Baptist and was mandated by Christ: "Thus it is written that the Messiah must suffer and rise from the dead on the third day. In his name, penance for the remission of sins is to be preached to all nations, beginning at Jerusalem" [Luke 24:46-47] Yet modern preaching, especially since the council has pretty much avoided the subject. Even in religious life, the concept of corporal penance had almost disappeared. The Lord's admonition, "It is mercy I desire, not sacrifice" may have been taken to the extreme in our days, yet the saints and the popes have taught that penance is a grace from the Divine Mercy.