Christian writer. He was perhaps originally a Jew. He enjoyed close relations with the royal house of Edessa and he went on a successful embassy from Emmaus to the Emp. Heliogabalus (218–22). His chief work was a ‘History of the World’ to ad 217, of which fragments are preserved in other writers. He held that the world would last for 6,000 years from the creation and that the birth of Christ took place in the year 5500.