The Holy Eucharist, which is known as the Divine Liturgy, is the central and most important worship experience of the Orthodox Church. Greek Orthodox Church Hierarchy. The three major orders in the Orthodoxy are: Bishops, Presbyters and Deacons. He is a special patriarch (which is often considered equal to an archbishop in various traditions, different only in honor). There is no single head here unlike the Pope of the Roman Catholic Church. Often referred to as the \"Sacrament of Sacraments\", it is the Church's celebration of the Death and Resurrection of Christ offered every Sunday and Holy day. Ecumenical Patriarch of Constantinople. The Greek Orthodox Church is a part of the spiritual union of the fifteen separate hierarchical churches which are recognized as the Orthodox Christian Churches. The first in honor among all Orthodox bishops (first among equals, as the Pope of Rome once was prior to schisming). But there is more or less consensus on the order and most orthodox Christians recognize the titles within the order and a negligible few are of a little different order. The Bishop is of the highest ranking but his rank is less of authority and more of honour and is … All the other Sacraments of the Church lead toward and flow from the Eucharist, which is at the center of the life of the Church. There is a discrepancy over the appointment of the metropolitans.