Theodore Abu Qurrah
Theodore Abū Qurrah (; ; c. 750, – c. 825) was a 9th-century Melkite bishop and theologian who lived in the early Islamic period. Biography. Theodore was born around 750 in the city of Edessa (Şanlıurfa), in northern Mesopotamia (Urfa, Turkey), and was the Chalcedonian Bishop of the nearby city of Harran until some point during the archbishopric of Theodoret of Antioch (795–812). Michael the Syrian, who disapproved of Theodore, later claimed that the archbishop had deposed Theodore for heresy, although this is unlikely. Between 813 and 817 he debated with the Monophysites of Armenia at the court of  Ashot Msakeri. Around 814 Theodore visited Alexandria. On his way, he sojourned at Sinai where, for one Abū 'l-Tufayl, he wrote the "Book of Master and Disciple" (now ascribed to "Thaddeus of Edessa"). He died between 820 and 825. Writings. Abū Qurrah was among the earliest Christian authors to use Arabic alongside Abu-Ra'itah of Tikrit, Ammar al-Basri and Abdulmasih al-Kindi. Some of his works were translated into Greek, and so circulated in Byzantium. He wrote thirty treatises in Syriac, but none of these have yet been identified. His writings provide an important witness to Christian thought  in the early Islamic world. A number of them were edited with German translations by Georg Graf and have now been translated into English by John C. Lamoreaux. Abū Qurrah argued for the rightness of his faith against the habitual challenges of Islam, Judaism and those Christians who did not accept the doctrinal formulations of the Council of Chalcedon, and in doing so re-articulated traditional Christian teachings at times using the language and concepts of Islamic theologians: he has been described by Sidney H. Griffith as a Christian "mutakallim". He attracted the attention of at least one Muslim Mu'tazilite  mutakallim, Isa ibn Sabih al-Murdar (died 840), who is recorded (by the biobibliographical writer, Ibn al-Nadim, who died in 995) as having written a refutation of Abū Qurrah. The subjects covered were, in the main, the doctrine of the Trinity, the Incarnation, and the Sacraments, as well as the practices of facing east in prayer (rather than towards Jerusalem or Mecca), and the veneration of the cross and other images. In Abū Qurrah's "Questions of Priest Musa", in the course of its first two discourses ("On the Existence of God and the True Religion") he used a  thought experiment in which he imagined himself having grown up away from civilization (on a mountain) and descending to 'the cities' to inquire after the truth of religion: an attempt to provide a philosophical argument in support of Chalcedonian Christianity from first principles. Theodore also translated the pseudo-Aristotelian "De virtutibus animae" into Arabic from Greek for Tahir ibn Husayn at some point, perhaps around 816.