The Orthodox Church is the original Christian Church, the Church founded by the Lord Jesus Christ and described in the pages of the New Testament. Her history can be traced in unbroken continuity all the way back to Christ and His Twelve Apostles.
Incredible as it seems, for over twenty centuries she has continued in her undiminished and unaltered faith and practice. Today her apostolic doctrine, worship, and structure remain intact. The Orthodox Church maintains that the Church is the living Body of Jesus Christ.
Many people are surprised to learn that for the first 1,000 years of Christian history there was just one Church. It was in the eleventh century that a disastrous split occurred between Orthodox East and Latin West. Although it had been brewing for years, the so-called “Great Schism” of 1054 represented a formal—and shocking— separation between Rome and Orthodoxy. At the core of the controversy were two vitally important areas of disagreement: the role of the papacy, and the manner in which doctrine is to be interpreted.
The Orthodox Church is an international federation of patriarchal, autocephalous, and autonomous churches. Each church is independent in her internal organization and follows her own particular customs. However, all the churches are united in the same faith and order. The Orthodox Church acknowledges that unity does not mean uniformity. Each Church is led by a synod of bishops. The president of the synod is known as the Patriarch, Archbishop, Metropolitan, or Catholicos. Among the various bishops, the Ecumenical Patriarch of Constantinople is accorded a "place of honor" and is regarded as "first among equals."
In America and Western Europe, where Orthodoxy is relatively young, there are a number of dioceses and archdioceses which are directly linked to one of these autocephalous Churches. For example, the Greek Orthodox Archdiocese is under the care of the Patriarchate of Constantinople. While the Archdiocese enjoys a good measure of internal autonomy and is headed by an Archbishop, it owes its spiritual allegiance to the Church of Constantinople.