He was a good-looking Irish lad
Those who didn't swoon chased him.
He was flattered and very much tempted, but his heart belonged to God, so he decided to become a monk (over the energetic objections of his mother).
For many years he devoted himself completely to prayer, reflection, and spiritual writing.
Then, he felt God call him to leave his refuge and to become a missionary. When he was sure that it was the Lord’s will, he and several of his fellow monks left Ireland to preach Christ in foreign lands.
The foreign lands were not happy to receive them. In fact, the Church was already there (although the fire of Christian devotion was not what it once was) and local clergy grumbled about the Irishmen. But, here and there, the monks were able to establish small monasteries from which they could work to evangelize the people anew.
Toward the end of his life, he retired to a small cave where he had built a chapel high above a river amid beautiful snowcapped mountains.
There, in the mountains of northern Italy, Saint Columbanus, son of Ireland and re-evangelist of Europe, died on November 21, 615. His memory is celebrated on this day.
(from a previous post)