Maximos was born in Sinope of Pontus in 1897. He learned his first letters at his birthplace and then went for further education to the Theological School of Chalki, under the protection of the metropolitan of Amaseia Germanos Karavaggelis. He was ordained a deacon in 1918 and appointed a teacher in the City School of Theira. He served as the Archdeacon of the metropolitans Gregorios of Chalcedon, Joachim of Ephesus, and in 1920 deacon in the Ecumenical Patriarchate. He became secretary of the Board of the School of Chalki, codewriter, subsecretary and archsecretary. He was ordained a presvyter and and archmandrite (1st January 1928), and became metropolitan of Philadelphia (February 1930).