Life and episcopate
According to his life, Leo was born at Ravenna of pious and noble parents and was educated there before being ordained to the priesthood. He was distinguished by benevolence and Christian love for the poor and for wanderers. One account relates that in his youth he became a monk and afterward moved to Reggio Calabria, where the bishop appointed him archdeacon.
He was elected bishop of Catania, by one reckoning in 765 and as the fifteenth bishop of that see. Throughout his episcopate he remained renowned for his care of those in need. Tradition further holds that during the period of Byzantine iconoclasm he opposed the destruction of holy images and for a time endured exile in the mountainous country of Sicily before returning to his bishopric.
Miracles & Traditions
Traditional Accounts: The best-known account of Saint Leo concerns the sorcerer Heliodorus, said to have come of a noble Christian family who renounced Christ and trafficked in magic, deceiving the people of Catania and Sicily through apparitions, spells, and charms. The synaxarion relates that Leo repeatedly admonished him to repent, but the sorcerer mocked the warnings and disrupted the church services. During the Liturgy, the tradition holds, Leo removed his omophorion, wrapped it about the sorcerer's neck, and led him out; a fire was kindled, and Leo entered the flames with him. Heliodorus was consumed, while Leo emerged unharmed, his vestments untouched.
Later accounts add that this wonder spread Leo's fame widely and that he was summoned to Constantinople, where further healings and signs were attributed to him. These episodes are transmitted as hagiographical tradition rather than as documented history.