After the death of the last Iconoclast emperor, Theophilos, his young son Michael III, with his mother the regent Theodora, and Patriarch Methodios, summoned the Synod of Constantinople in 842 to bring peace to the Church.
John's namesake grandfather had been a commander of the elite Hikanatoi regiment (tagma) under Emperor Basil I (reigned 867–886); John's brother Theophilos became a senior general, as did John's own son, Romanos, and his great-nephew, John Tzimiskes.
He was ordained as Deacon by Mor Gregorios Geevarghese Metropolitan in 1989, as priest by the Catholicos of the East, Baselios Thomas I in 2002 and in 2003 he was ordained as metropolitan with the name Mor Theophilos.
In the aftermath of the sack of Amorium, Theophilos sought the aid of other powers against the Abbasid threat: embassies were sent to both the western emperor Louis the Pious (r. 813–840) and to the court of Abd ar-Rahman II (r. 822–852), Emir of Córdoba.