Orthodox Church

Federation of national and regional self-governing Christian churches, mainly found in Eastern Europe and parts of Asia. The final schism between the Orthodox Church and the Roman Catholic Church occurred in 1054. The centre of worship is the Eucharist. Clergy, other than the bishops, may marry, and the Immaculate Conception is not accepted. The highest rank in the church is that of ecumenical patriarch, or bishop of Istanbul. There are (1990) about 130 million adherents.

The church's teaching is based on the Bible, and the Nicene Creed (as modified by the Council of Constantinople 381) is the only confession of faith used. The celebration of the Eucharist has changed little since the 6th century. The ritual is elaborate, and accompanied by singing in which both men and women take part, but no instrumental music is used. Besides the seven sacraments, the prayer book contains many other services for daily life. During the marriage service, the bride and groom are crowned.

Orthodox churches are in most countries throughout the world, but are probably strongest in Eastern European countries, especially Russia. Its adherents include Greeks, Russians, Romanians, Serbians, Bulgarians, Georgians, and Albanians. In the last 200 years, the Orthodox Church has spread into China, Korea, Japan, and the USA, as well as among the people of Siberia and central Asia. Some of the churches were founded by the apostles and their disciples; all conduct services in their own languages and follow their own customs and traditions, but are in full communion with one another. There are many monasteries, including one on Mount Athos in Greece, which has flourished since the 10th century. The senior church of Eastern Christendom is that of Constantinople (Istanbul).