His father was János Kossey, a priest, and his mother was Márta Jaromisz. His wife was Kornélia Jolán Artimovics; they had 12 (or, according to other sources, 13) children, one of whom, János, served as an Orthodox priest. He pursued his theological studies in Uzhhorod. He was ordained a priest on December 27, 1899, by Bishop Gyula Firczák of Munkács. He served in the United States beginning in 1905.