JERUSALEM, Jan 13 (Reuters) - A 92-year-old Israeli rabbi who serves as the spiritual head of a powerful ultra-Orthodox political party was released from hospital on Sunday after treatment for a suspected minor stroke. Rabbi Ovadia Yosef, who has largely set the terms under which his Shas party has agreed to join a succession of governments, was taken to Jerusalem's Hadassah hospital by ambulance on Saturday after feeling weak during sabbath prayers.