John bar Qursos, bishop of Tella was one of the leading Syrian Orthodox bishops of the sixth century. He became bishop of Tella d-Mawzlat (today: Viranşehir, a city in south-eastern Turkey) in the Roman province of Osrhoene in 519, but left for exile only two years later when the emperor Justin I (518-527), the uncle of Justinian I (527-565), enforced the Council of Chalcedon which the Syrian Orthodox Christians refused to accept as an ecumenical council. John established himself as one of Justinian’s most dangerous ecclesiastical opponents by ordaining thousands of deacons and priests who formed the first generation of the Syrian Orthodox ecclesiastical hierarchy, against the ruling Chalcedonian church of the empire. John also took great care in instructing his clergy properly according to church law, and Canons, Questions and Answers etc. written by him for priests and deacons have survived. The present text is a letter by John, probably written at the end of his life in 536/7, in which he lays out his faith. The text gives an inside view of how a Syrian Orthodox bishop of the sixth century located himself and his fellow non-Chalcedonian Christians within the Christian tradition and how he understood the foundation of the Church - a perception which stood in contrast to both the papal view as well as the eastern Chalcedonian understanding of the Christian past.