4 Bonosus, your friend, or, to speak more truly, mine as well as yours, is now climbing the ladder foreshown in Jacob's dream. He is bearing his cross, neither taking thought for the morrow nor looking back at what he has left. He is sowing in tears that he may reap in joy. As Moses in a type so he in reality is lifting up the serpent in the wilderness. This is a true story, and it may well put to shame the lying marvels described by Greek and Roman pens. For here you have a youth educated with us in the refining accomplishments of the world, with abundance of wealth, and in rank inferior to none of his associates; yet he forsakes his mother, his sisters, and his dearly loved brother, and settles like a new tiller of Eden on a dangerous island, with the sea roaring round its reefs; while its rough crags, bare rocks, and desolate aspect make it more terrible still.
No peasant or monk is to be found there. Even the little Onesimus you know of, in whose kisses he used to rejoice as in those of a brother, in this tremendous solitude no longer remains at his side. Alone upon the island— or rather not alone, for Christ is with him— he sees the glory of God, which even the apostles saw not save in the desert. He beholds, it is true, no embattled towns, but he has enrolled his name in the new city. Garments of sackcloth disfigure his limbs, yet so clad he will be the sooner caught up to meet Christ in the clouds. No watercourse pleasant to the view supplies his wants, but from the Lord's side he drinks the water of life. Place all this before your eyes, dear friend, and with all the faculties of your mind picture to yourself the scene.
When you realize the effort of the fighter then you will be able to praise his victory. Round the entire island roars the frenzied sea, while the beetling crags along its winding shores resound as the billows beat against them. No grass makes the ground green; there are no shady copses and no fertile fields. Precipitous cliffs surround his dreadful abode as if it were a prison. But he, careless, fearless, and armed from head to foot with the apostle's armor, now listens to God by reading the Scriptures, now speaks to God as he prays to the Lord; and it may be that, while he lingers in the island, he sees some vision such as that once seen by John.
Source: Letters (New Advent)