Elias was a Malkite, who after reading the writings of Severus of Antioch, embraced the Syrian Orthodox faith. He became a monk at the Outer Gubba Monastery (ܓܘܒܐ ܒܰܪܳܝܐ). Because of his piety and learning, he was ordained bishop of Apamea around 691. Later he was elevated to the Holy See of Antioch in 709. He entered Antioch in great pomp and was greatly honored by the Umayyad Caliph al-Walid. Elias was very scrupulous in attending per­sonally to the affairs of his congregation. He died in 723 at eighty-two years of age.

Of his writings that have come down to us is a lengthy letter which he wrote while still a bishop, in reply to Leo, the Malkite bishop of Harran, apologizing for forsaking the doctrine of the Two Natures. In this letter, divided into twelve chapters and covering forty pages, Elias refuted the questions raised by Leo and proved with evidence the soundness of his newly-embraced doctrine. He also combined an apology and a disputation, citing as testimonies famous church Doctors, such as, Athanasius, Gregory Nazianzen, Gregory of Nyssa, Ambrose and Cyril. He also cited the Syrian Mor Simon d-Zayte; and the Malkite Bishops John of Damascus, George, bishop of Miyafarqin (today Siverek in Turkey), and Constantine of Harran. A complete copy of this letter is at the Vatican Library, with a table of contents containing the titles of chapters. Another version which is imperfect is in the British Museum, written on vellum in the Estrangelo script. Of this version portions of chapter seven as well as the last four chapters survive. Also at the British Museum is an extracrt of the letter of Patriarch Elijah to the clergy of the village of Ruhin, in the province of Antioch. In writing it, he was assisted by Mor George, bishop of the diocese of Ruhin.