Jacob was born in c. 500 in the city of
Constantia (close to modern day
Viranşehir), and was the son of Theophilus bar Manu, a priest. and studied Greek, Syriac, and religious and theological texts. Jacob's mother later returned to the monastery and attempted to bring him home, however, Jacob refused to return and declared his dedication to Christ. After his parents' death, Jacob donated his inheritance to the poor and manumitted several slaves he had inherited, to whom he bestowed his parents' house. Theodora received Jacob with honour, however, he was uninterested in life at court, An outbreak of persecution of non-Chalcedonians carried out by
Ephraim, Patriarch of Antioch, spurred Empress Theodora and Al-Harith to urge
Pope Theodosius I of Alexandria to consecrate bishops to counter Ephraim and ensure the survival of non-Chalcedonianism. At this time, through his missionary work, Jacob aimed to restore non-Chalcedonianism as the official position of the church in the Eastern Roman Empire. Jacob ordained
John of Ephesus as Bishop of
Ephesus in 558. In 559, Jacob consecrated
Ahudemmeh as
Metropolitan of the East. In 566, Jacob attended discussions held by Emperor
Justin II at Constantinople between Chalcedonians and non-Chalcedonians with the goal of a compromise between the two factions. At the end of the discussions in 567, Justin issued an edict which was agreed upon by all who attended, however, the edict was rejected by a non-Chalcedonian council at
Raqqa. Jacob and the other bishops subsequently accepted communion from
John Scholasticus, Ecumenical Patriarch of Constantinople. Some historians note the name of the monastery as the Monastery of Cassian. ==References==