. Jacob was the son of prince Gefal, Jacob became famous, and received visits from Sheria,
Bishop of Arbela (r. 304–316), according to the
Chronicle of Arbela. It is stated in legend that Jacob resolved to climb
Mount Qardu, traditionally believed to be the resting place of
Noah's Ark, and recover a fragment of the ark upon hearing from the hermit
Maroukeh that local people doubted the
Great Flood. Jacob ascended the mountain and rested close to the summit; in his sleep, an angel placed a fragment of the ark close to him, and instructed him to awake. Also, in one incident, Jacob cursed boastful, promiscuous women by a spring so that their hair became white, and the spring disappeared. The women subsequently repented, and the spring returned, however, the women's hair remained white. However, Jacob is credited as the successor of Babu, the first bishop of Nisibis (r. 300–309), by the
Catholic Encyclopedia, who Ephrem states was in fact Jacob's successor. Jacob attended the funeral of
Metrophanes of Byzantium in 326. Jacob was present at the siege of Nisibis by
Shapur II,
Shahanshah of
Iran, in 337/338, and according to Theodoret, with encouragement from the city's population and Ephrem, Jacob ascended the walls and prayed for the city, and cursed the besiegers. The
Martyrologium Hieronymianum relates that he died on 15 July, the thirtieth day of the siege, according to the
Chronicle of 724. Gennadius and Ephrem record that Jacob was buried within the walls of Nisibis. Shapur II challenged him to fight outside the city, where it was revealed he was an apparition and the Iranian army withdrew as a result. ==Relics==