John Hylilas

John VII, surnamed Grammatikos or Grammaticus, i.e., "the Grammarian" (Greek: Ιωάννης Ζ΄ Γραμματικός, Iōannīs VII Grammatikos), Ecumenical Patriarch of Constantinople from January 21, 837 to March 4, 843, died before 867. He is not to be confused with the much earlier philosopher John Philoponos.

John was born to an aristocratic family of Armenian origin. His father was Pankratios Morocharzanios and he had a brother, Arsaber. Warren Treadgold identifies the latter with the Arsaber who married a sister of the Empress Theodora. John's sister was the mother of the later Patriarch Photios. Beginning his clerical career in c. 811, John was also a painterof icons and a correspondent of Theodore of Stoudios. By 814, John had become an Iconoclast and Emperor Leo V chose him to lead a committee to collect patristic texts supporting this theological position in preparation for the synod of 815, which reinstituted Iconoclasm. John was rewarded for his troubles by being appointed abbot of the prestigious Sergios and Bakchos monastery, where recalcitrant Iconodules were being re-educated.

John was renowned for his learning (hence the nickname Grammatikos), and for his persuasive rhetoric in the endless debates that are a favorite subject of hagiographic sources reflecting the second period of Iconoclasm. John was also charged with tutoring the future Emperor Theophilos during the reign of his father Michael II, and is credited with instilling strong Iconoclast sympathies in his student. On the accession of Theophilos, John was appointed synkellos (patriarch's assistant), a position that made him a likely heir to the patriarchate. In c. 830, John was dispatched on an embassy to the Caliph al-Ma'mun, but this did little to prevent a period of fierce warfare between the Byzantine Empire and the Abbasids. He did, however, bring back a plan of the Abbasid palace at Baghdad for the amusement of his emperor and supervised the building of a similar structure in Bithynia.

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