Like the Catholic Church, the Orthodox Church is an institution whose first churches have known unbroken continuity, and they have adopted the same sacred ceremonies. The split between the two churches, Western and Eastern, stems more from political and cultural differences than disagreements on theology. From the cultural standpoint, the divergence of Western Christianity from Orthodox is an extension of the division brought about by Latin being the prevailing language in the Western Roman Church, while in the Eastern Byzantine Church the written language is Greek.
In the 5th century after the disappearance of the Western Roman Empire, the Pope, who until then had held honorary supremacy over all churches, now assumed imperial powers to a large extent. Although the Patriarch in Constantinople was head of the Church, he was never able to gain independence such as that enjoyed by the Pope, so long as total power was in the hands of the emperor. The Eastern Church’s insistence that the Holy Ghost derived only from God the Father was accused by the West of being a heresy. In 1054, the Pope and the Patriarch excommunicated each other, and an irreversible schism took place. The sacking of Constantinople during the Fourth Crusade in 1204, rendered impossible any effort at unification, and neither Church acknowledged the other until as late as 1965.
The Orthodox and Roman Catholic Churches as well as Muslim organizations preserved their identities in the face of Communist regimes. The Orthodox Church consists of a number of self-governing churches, the oldest of which are the Greek Orthodox and those governed by the Patriarchs of Alexandria, Antioch (Antakya), and Jerusalem. The Patriarch of Istanbul enjoys primacy of honour but has no universal jurisdiction. Orthodox churches are predominant in the Balkans, the Slav countries and parts of the Middle East. Like the Protestant Church, the Orthodox does not recognize the Roman Papacy.
Orthodox bishops and monks are obliged to remain celibate, but priests are permitted to marry.
In Orthodox services, Mary is referred to as the Mother of God. The Holy Thursday service is performed to commemorate the Last Supper and the washing of the disciples’ feet. Priests wear beards as specified in the Bible. Musical instruments are not allowed in the churches and there are no statues. Music is provided by singing in the choir, and walls are decorated with pictures, frescoes and mosaics. The church’s most lavish decor is the iconostasis.