Seized by pirates as a boy, converted by the hermit who took him in, he followed him into the cloister.
Tradition has him born around 980 in British Cornwall. As an adolescent he was seized by pirates who scoured insular Brittany and served them as a ship’s boy, before being abandoned wounded on an island. Felix, a hermit of Ushant, took him in, tended him and converted him; when Felix came to restore the abbey of Saint-Gildas-de-Rhuys in 1008, Gustan joined him as a lay brother, then took the monastic habit there. He spent the greater part of his life there, charged with hospitality and provisioning, which often obliged him to cross the gulf: the sailors and fishermen of the Morbihan took him as their patron because of those crossings. With Felix’s leave he kept a hermitage for a time on the island of Hoëdic. He died around 1040 at the priory of Beauvoir-sur-Mer, in Poitou, which Rhuys had founded there. His cult never passed beyond the Rhuys peninsula, where his pardon is still kept.
A Benedictine monk by a boat or a shore; sometimes a fish, or the chains of his captivity.