From Sicily to Greece
By the accounts Joseph was born in Sicily around the year 816 to Christian parents named Plotinus and Agatha. While he was still a child or youth, the Arab invasions of Sicily forced the family to abandon the island and resettle in Greece, a displacement the synaxarion records among the hardships of his early life.
Settling in the region of Thessalonica, he was tonsured a monk at the monastery of Latomos and in time was ordained a priest. His gifts drew the attention of Saint Gregory the Dekapolite, who brought him to Constantinople, where the two stood together in defense of the holy icons during the iconoclast controversy that troubled the Church in that age.