Ishoʿyahb II of Gdala was Patriarch of the Church of the East from 628 to 645. He reigned during a period of great upheaval in the Sasanian Empire. He became patriarch at the end of a disastrous war between Rome and Persia, which weakened both powers. Two years later the Moslem Arabs began a career of conquest in which they overthrew the Sassanian empire and occupied the eastern provinces of the Roman empire. Ishoʿyahb lived through this momentous period, and is said to have met both the Roman emperor Heraclius and the second Moslem caliph ʿUmar ibn al-Khattab. The Syriac name Ishoʿyahb means 'Jesus has given', and is spelled variously in English. Alternative spellings include Yeshuyab and Ishu-yahb. Ishoʿyahb II is commonly known as Ishoʿyahb of Gdala, to distinguish him from two near-contemporary Nestorian patriarchs, Ishoʿyahb I of Arzun (582–95) and Ishoʿyahb III of Adiabene (649–59). Sources Ishoʿyahb's patriarchate, the Arab conquest of Iraq and Ishoʿyahb's dealings with the Moslem leaders are described in considerable detail in the Chronicle of Seert. Briefer accounts are given in the Ecclesiastical Chronicle of the Jacobite writer Bar Hebraeus (thirteenth-century), and the ecclesiastical histories of the Nestorian writers Mari (twelfth-century), ʿAmr (fourteenth-century) and Sliba (fourteenth-century). Life Ishoʿyahb was a native of the village of Gdala in the district of Beth ʿArbaye between Nisibis and Mosul. Ishoʿyahb studied at the School of Nisibis when it was under the presidency of the controversial theologian Hnana, who searched for common theological ground between the Nestorianism of the Church of the East and the Chalcedonian doctrines held in the Roman empire. He was one of the 300 students who left the college when Hnana was expelled. After a long vacancy in the patriarchate, he was elected patriarch of the Church of the East in 628. In 630 Ishoʿyahb led a delegation of Persian clerics to Aleppo to discuss with the Roman emperor Heraclius the possibility of a reconciliation between the Roman and Persian Churches. Although little is known of the content of Ishoʿyahb’s discussions with Heraclius, he evidently persuaded the emperor that, despite its traditional reverence for the teachings of Theodore of Mopsuestia, the doctrinal position of the Church of the East was orthodox. He was asked for his views on monoenergism, the doctrine of the single energy recently espoused by the patriarchate of Constantinople, and responded with a confession of faith which was accepted by the Roman