He was one of the best patriarchs of Antioch because of his zeal, piety and good judgment. Natives of Samosata, Athanasius and his brother Severus were brought up after the death of their father by their pious and virtuous mother. Later the two brothers became monks at the Monastery of Qinnesrin. At the monastery, Athanasius was known as the Gamolo (camel driver), because he used to deliver salt from mine at Jabboul Saltery in Aleppo to his Monastery (Qinneshrin) by Camels, in compliance with its regulations.

Upon departure of the patriarch Julian I (591-595), the Metropolitans of the Holy synod of Antioch, gathered in the monastery to elect a new patriarch for the Holy See. One of the Metropolitans was told by God in the dream that the new patriarch has chosen by Him (God), the first monk who will knock on the door of the monastery early morning, he is the one that chosen by God. In the early morning when the door of the monastery was opened they saw Athanasius the monk who came with his camels to bring salt to his monastery (Qinneshrin), they took him and was told by the Metropolitan that God has chosen him to become a patriarch, he humbly refused to accept, but they laid there hands on him and consecrate him Patriarch, and thus He was chosen a patriarch for the Holy See of St. Peter in 595, and he administered the church from 595 to 631 the year he died in.

Athanasius wrote three noble general letters: one addressed to Cyriacus, metropolitan of Amid, describ­ing the unity which he held with the See of Alexandria, the second letter was to the abbot and monks of St. Matthew's monastery and the third letter to the Emperor Heraclius, in which he refuted the heresy of john Grammaticus. He also wrote a discourse containing the biography of Severus (of Antioch) in which he elaborated on his struggle. This biography, whose original Syriac has been lost, survives in the Ethiopic translation, which was rendered into English and published by Goodspeed. It was also mentioned by the historians of the patriarchs of Alexandria.

(History of Syriac Literature and Sciences, Patriarch Ignatius Ephrem I Barsoum, Presseggiata Press, p 105)