Butrus (Peter) Saba was the son of the priest Abu al-Hasan, son of Saliba, son of the priest Behnam of the village of
Salah. He was the nephew of the bishops Basil Barsoum and Aziz, archbishop of Salah. Saba was consecrated as archbishop of Salah by the Patriarch
Ignatius Ismail of
Mardin in 1354, upon which he assumed the name Basil. In 1364, Ismail heard criticism of Saba from a monk named George, and promptly excommunicated Saba without investigation. Saba attempted to speak with Ismail at the patriarchal residence at the
monastery of Saint Ananias, but was rebuked and refused entry. After having waited at the gate of the monastery for three days, he left and rallied support for his cause by writing letters to the bishops of
Tur Abdin. Saba returned to the patriarchal residence, accompanied by a number of notables and clergymen, including the bishops Yuhanna Yeshu of
Qartmin and Philoxenus of
Hah, but he was again refused entry and waited outside the monastery for four days. Saba's supporters resented Ismail's inaction and proclaimed him as patriarch at his residence at the monastery of Saint Jacob at Salah, in opposition to Ismail's patriarchate of Mardin. He received a decree from al-Malik al-Adil Fakhr al-Din Sulayman I al-Ayyubi,
Melik of Hasankeyf, thereby confirming his patriarchate within his domain, and Saba was consecrated as
Patriarch of Tur Abdin and
Hasankeyf on the
Feast of the Transfiguration on 6 August in the same year, upon which he assumed the name Ignatius. Saba's ascension as patriarch of Tur Abdin has been noted to reflect the political division between the
Artuqid emirate of Mardin and
Ayyubid emirate of Hasankeyf. He served as patriarch of Tur Abdin until his death in 1389, and he was buried at the monastery of Saint Jacob at Salah. ==Episcopal succession==