After leading the Celtic monastery of Lismore and traveling on pilgrimage to the Holy Land, he is said to have arrived in Taranto as a pilgrim by divine invitation, dedicating himself to the re-evangelization of a city that was then largely pagan. The discovery of his relics, on May 10, 1071, during the reconstruction of the cathedral destroyed by the Saracens, marked the birth of a cult that made him the patron saint in Apulia and was later introduced in Sicily: the village that grew around a small church dedicated to him thus took the name of San Cataldo, in honor of a bishop renowned for his spirit of sacrifice and charity toward the poor.