Tatian (110-180) was an early Christian apologist, probably born in Syria. "He was a pupil of Justin Martyr. After his master’s death, he left Christianity, becoming an Encratitic Gnostic — i.e., he regarded all matter as evil and denied the salvation of Adam. While a Christian, he wrote Oratio ad Graecos (Address to the Greeks) (152–55), a defense of Christianity bolstered by a bitter attack on Greek arts, philosophers, and institutions, and the Diatessaron, a harmony of the four Gospels that was long the only life of Jesus available in Syria." (The Columbia Encyclopedia, Sixth Edition)