St. Gregory the Theologian has left a rich literary heritage, which was translated into Armenian in the 5th to 8th centuries AD. In all probability, St. Moses of Khoronk created part of the translations into Armenian. St. Gregory the Theologian is one of the most prominent figures of Christianity, who by means of the struggle against Arians, kept Christianity uncorrupted and by means of his works he has greatly influenced the formulation of the Christian theologian ideology.
St. Gregory the Theologian was born in 328 AD in the village Ariangue near the town of Naziangue, of Cappadocia. He was the son of the Bishop Gregory. Gregory studied in Caesaria, and then in Athens. In Athens Gregory became acquainted with St. Barsegh of Ceasaria, one of the future prominent figures of Christianity. After leading an ascetic life for a while, Gregory returned to Naziangue, where he was ordained as a priest by his father. Later he became the Bishop of Sasima. Together with St. Barsegh of Ceasaria, St. Gregory the Theologian struggled against the Arians. He participated in the 2nd Ecumenical Council of Constantinople. St. Gregory passed away on 25 January 389 AD.