Eastern Orthodoxy

Overview

Eastern Orthodoxy is the family of Christian churches that see themselves as continuing the church of the apostles and hold to the faith defined by seven ecumenical councils between 325 and 787. It grew up in the Greek-speaking Eastern Roman, or Byzantine, Empire, whose capital, Constantinople (now Istanbul), was its centre for over a thousand years. There is no pope: Orthodoxy is a communion of self-governing churches, from Russia, Ukraine, Romania, Serbia, Greece and Georgia to the ancient patriarchates of the Middle East, which give the Ecumenical Patriarch of Constantinople a primacy of honour. Its worship is known for icons and unaccompanied chant, and its spirituality aims at theosis, a sharing in God's life. It is distinct from the Oriental Orthodox churches, which parted from it after 451.^[11–15]

History

Empire and councils 4th–9th century

After granting Christians toleration in 313, the emperor Constantine refounded Byzantium in 330 as Constantinople, his new capital. Seven ecumenical councils, from Nicaea in 325 to a second council there in 787, defined the doctrine of the Trinity and of Christ, and the Orthodox still hold their decisions binding. After Chalcedon in 451, many Christians in Egypt, Syria and Armenia rejected its wording on Christ's two natures, the split behind today's Oriental Orthodox churches. From the 720s emperors outlawed the veneration of icons in two waves, until the empress Theodora restored them for good in 843.^{[3, 16–18]}

Missions to the Slavs 9th–11th century

The church of Constantinople spread far beyond the empire. In 863 two brothers from Thessalonica, Constantine (later Cyril) and Methodius, reached Moravia with a new Slavonic alphabet and Slavonic scripture and liturgy. Bulgaria became Orthodox in the 9th century, and in 988 Prince Vladimir of Kyiv was baptised, bringing Rus' into the Byzantine church. Monks organised on Mount Athos from the 960s, gaining an imperial charter in 972. Justinian's Hagia Sophia, built in 532–537, set the pattern of worship for the Orthodox world.^[19–22]

East and West drift apart 9th–15th century

Greek East and Latin West drifted apart over language, the pope's claim to authority over the whole church, and the Filioque, a Western addition to the creed. In 1054 papal legates and Patriarch Michael Cerularius excommunicated each other, but historians now see that year as one episode in a slow estrangement. The rift hardened in 1204, when crusaders sacked Constantinople and installed a Latin patriarch. A reunion signed at Florence in 1439 was disowned by most Orthodox, and on 29 May 1453 the city fell to the Ottoman sultan Mehmed II, who made Hagia Sophia a mosque.^[23–26]

Under sultans and tsars 1453–1917

The sultans made the Ecumenical Patriarch head of the Rum millet, the community of all their Orthodox subjects, with civil as well as spiritual powers. Russia, the one major Orthodox land outside Ottoman rule, chose its own metropolitan in 1448 and gained a patriarch in 1589; some Russians called Moscow the 'third Rome'. Patriarch Nikon's reforms of the 1650s split off the Old Believers, and in 1721 Peter the Great replaced the patriarch with a state-run Holy Synod. As Balkan nations won independence, their churches became autocephalous, Greece's from 1833 and Serbia's in 1879.^[27–30]

Revolution and repression 1917–1991

A Moscow council restored the Russian patriarchate in 1917, electing Tikhon as the Bolsheviks took power. Soviet decrees stripped the church of property and legal rights, and under Stalin thousands of clergy and believers were killed; Britannica reports that by 1939 only about 100 churches functioned openly. Stalin eased pressure in wartime, allowing a patriarch to be elected in 1943, but Khrushchev's campaign from the late 1950s closed about half the open churches again. Communist regimes curbed the Balkan churches, and Albania began closing every church in 1967. Emigrants meanwhile planted Orthodoxy in western Europe and the Americas.^[31–35]

Revival and rupture 1991–today

After communism fell, churches reopened; Pew estimates that Russia's Orthodox population has passed 100 million. Jurisdiction became the new fault line. In October 2018, after Constantinople moved to recognise an independent church in Ukraine, the Russian church broke communion with it; in January 2019 Patriarch Bartholomew I granted the Orthodox Church of Ukraine its tomos of autocephaly, which Moscow calls uncanonical. Ukraine's other large church, long tied to Moscow, declared independence in May 2022; the authorities doubt the break, and a 2024 law lets the state dissolve bodies it finds tied to the Russian church. Regulators then sued to dissolve the church's Kyiv Metropolis; it disputes the finding, and the case was unresolved in 2026. In 2025 Bartholomew and Pope Leo XIV prayed together at ancient Nicaea.^[36–39]

Key moments

1. 537 CEHagia Sophia · Constantinople (Istanbul)
2. c. 726 CEByzantium bans its icons · Constantinople
3. c. 863 CECyril and Methodius among the Slavs · Great Moravia (Czechia and Slovakia)
4. c. 957 CEOlga of Kyiv is baptised · Kyiv and Constantinople
5. 988 CEThe Baptism of Rus' · Kyiv
6. 1054 CEThe Great Schism · Constantinople and Rome
7. 1095 CEThe First Crusade · Clermont to Jerusalem
8. 1204 CECrusaders sack Constantinople · Constantinople
9. 1453 CEConstantinople falls · Constantinople (Istanbul)
10. 1918 CEThe Soviet campaign against religion · Petrograd and Moscow, Russia

Beliefs

Holy Trinity · Ἁγία Τριάς

Orthodox Christians confess one God in three persons, Father, Son and Holy Spirit, and, following the Greek Fathers, hold that the Father alone is the source of the Son and the Spirit. They recite the creed of 381 in its original form, rejecting the Filioque, 'and from the Son', because the West changed a council's creed on its own and, they believe, blurred the persons.^[40–41]

Theosis · θέωσις

deification

Orthodox teaching holds that human beings, made in God's image, are called to share in God's own life. Salvation is pictured less as a legal pardon than as union with God, begun in baptism and continuing after death. This never makes a person God by nature: Orthodox theology says God's essence stays unknowable, while people share in his energies. Councils in 1341–1351 upheld this distinction, defended by Gregory Palamas.^[42–44]

Theotokos · Θεοτόκος

God-bearer

With Chalcedon, the Orthodox confess Christ as one person, fully God and fully human. They therefore call Mary Theotokos, a title upheld at Ephesus in 431, and honour her above all the saints.^[45]

Icons · εἰκόνες

Because God became visible in Christ, the Orthodox hold that Christ, Mary and the saints may rightly be depicted. Icons are venerated, not worshipped: prayer passes through the image to the person shown. The council of 787 affirmed this against the Iconoclasts.^[46]

Holy Tradition

Orthodoxy reads the Bible within Tradition: the creeds and councils, the Church Fathers and the liturgy. Authority lies with bishops in council rather than a single head.^[47–48]

Practice

The Divine Liturgy · Θεία Λειτουργία

The Sunday Eucharist usually follows the liturgy attributed to John Chrysostom, with Basil's used on certain days. It is chanted without instruments before an iconostasis, and worshippers often stand throughout. Communion is leavened bread and wine, given together from a spoon.^[49–50]

The holy mysteries

The sacraments are called mysteries. Infants are baptised by triple immersion, anointed at once with chrism (chrismation) and then given communion. Confession, anointing of the sick, marriage by a rite of crowning, and ordination are also mysteries.^[51–52]

Fasting

The church year sets fasting seasons, above all Great Lent before Easter. Practice varies: Pew found most Orthodox in Greece, Serbia and Romania fasting in Lent, but not in most former Soviet republics.^[53–54]

Icons, candles and the cross

Most Orthodox homes keep icons, often in a prayer corner with a lamp; in Pew surveys over nine in ten Orthodox in Greece and Romania said they had icons at home. Lighting candles in church and crossing oneself with thumb and two fingers joined are everyday devotions.^[55–56]

Monasticism and the Jesus Prayer

Celibate monks and nuns follow traditions begun in Egypt in the 3rd and 4th centuries, and bishops come from the unmarried clergy, while most parish priests are married. The hesychast way of prayer centres on the Jesus Prayer, a constant calling on Jesus' name, sometimes paced with the breath.^[57–58]

Holy days

Pascha (Easter) · Πάσχα

Sunday after the spring full moon, by the Julian reckoning (March–May)

The Feast of Feasts, celebrating Christ's resurrection, after the fast of Great Lent. Because the Orthodox compute it with the Julian calendar, and keep it after the Jewish Passover, it usually falls later than the Western Easter.^[59]

Nativity of Christ

25 December; 7 January (Gregorian) in Julian-calendar churches

Christmas follows the Nativity Fast. Churches that keep the Julian calendar celebrate it on 25 December by that calendar, which now falls on 7 January in the Gregorian.^[60]

Theophany · Θεοφάνεια

6 January; 19 January (Gregorian) in Julian-calendar churches

Marks Christ's baptism in the Jordan, seen in the East as his manifestation as both God and man. Priests perform the Great Blessing of Waters, and the faithful may take holy water home.^[61]

Sunday of Orthodoxy

First Sunday of Great Lent (February–March)

Commemorates the restoration of icons to the churches in 843, at the end of the iconoclast controversy, and is kept as a feast of the Orthodox faith itself.^[62]

People

John Chrysostom

saint · c. 347–407

A preacher from Antioch who became archbishop of Constantinople in 398. His sermons for the poor and against the misuse of wealth earned him the name Chrysostom, 'golden-mouthed'. Enemies at court had him exiled, and he died in exile. The most-used Orthodox liturgy bears his name.^{[49, 63]}

John of Damascus

scholar · c. 675–749

A monk of Mar Saba near Jerusalem whose treatises defended icons against the iconoclast emperors; a council of 754 condemned him, and Nicaea II reversed it. His Fount of Knowledge became a standard textbook of Greek theology, and hymns of his are still sung from the Octoechos.^[64]

Cyril and Methodius

saint · 9th century

Brothers from Thessalonica sent by the Byzantine emperor to Moravia in 863. Constantine, later Cyril, devised the Glagolitic alphabet, and together they translated scripture and liturgy into Slavonic, laying foundations for Slavic Orthodoxy.^[19]

Gregory Palamas

teacher · 1296–1359

A monk of Mount Athos who defended the hesychasts' prayer and their claim to see God's uncreated light against Barlaam of Calabria. He became archbishop of Thessalonica, councils upheld his teaching, and he was proclaimed a saint in 1368.^[65]

Sergius of Radonezh

saint · 1314–1392

A Russian monk who founded the Trinity monastery north-east of Moscow. He blessed Prince Dmitry Donskoy before the battle of Kulikovo in 1380, and his disciples spread monasteries across northern Russia. He is among Russia's most venerated saints.^[66]

Bartholomew I

other · born 1940

Ecumenical Patriarch since 1991, born on the island of Imbros (Gökçeada), Turkey. Known as the 'Green Patriarch' for his environmental work, he won the Templeton Prize in 2025. In 2019 he recognised the Orthodox Church of Ukraine as autocephalous.^{[37, 67]}

Scripture

The Bible

Orthodox Bibles take their Old Testament from the Septuagint, the ancient Greek translation, so they include books Protestants class as Apocrypha. They also include some books not in Catholic Bibles, and the exact contents vary between Orthodox churches. The New Testament has the usual 27 books.^[68]

The Nicene-Constantinopolitan Creed

325, revised 381

The statement of faith of the first two ecumenical councils, sung or said at every Divine Liturgy in its original wording, in which the Spirit proceeds from the Father, without the Filioque.^[69]

The Philokalia · Φιλοκαλία

1782

An anthology of Greek monastic writings on prayer, from Evagrius to Gregory Palamas, compiled by Nicodemus of the Holy Mountain and Macarius of Corinth and printed at Venice in 1782. A Slavonic version of 1793 spread the Jesus Prayer across Russia.^[70]

Places

Hagia Sophia, Istanbul

TUR · UNESCO World Heritage, 1985

Justinian's Church of Holy Wisdom (532–537) was the cathedral of Constantinople and the model for Orthodox church design. It became a mosque in 1453, a museum in 1935 and a mosque again in 2020, within the Historic Areas of Istanbul World Heritage property.^[71]

Mount Athos

GRC · UNESCO World Heritage, 1988

The Holy Mountain, a self-governing monastic peninsula in northern Greece under the Ecumenical Patriarch's spiritual oversight, with 20 monasteries and some 1,400 monks; women are barred. The point is Karyes, its capital; the whole peninsula is a World Heritage Site.^[72]

Kyiv-Pechersk Lavra and St Sophia, Kyiv

UKR · UNESCO World Heritage, 1990

The Monastery of the Caves, founded in the 11th century by Saints Anthony and Theodosius, and St Sophia's Cathedral, with its 11th-century mosaics, are great monuments of Kyivan Rus' and one World Heritage property. The point marks the Lavra.^[73]

Trinity Lavra of St Sergius, Sergiev Posad

RUS · UNESCO World Heritage, 1993

Founded by Sergius of Radonezh in the 14th century about 70 km north-east of Moscow, it is the Russian church's most important working monastery and a major pilgrimage site.^[74]

St Catherine's Monastery, Sinai

EGY · UNESCO World Heritage, 2002

Founded in the 6th century at the foot of the mountain where, the Bible says, Moses received the Law, and in monastic use ever since. Its manuscripts and icons, some of the few to survive Iconoclasm, are famous.^[75]

Art & objects

Public-domain objects from museum collections. Select one to see it at the museum.

Solidus (Coin) of Basil I with Christ EnthronedByzantine Empire, 868–870Pilgrimage Jug with Christian SymbolsLatin Kingdom of Jerusalem, 578–636Christ in Majesty surrounded by the Fathers of the Church with Scenes from the Life of ChristRussia, 17th–18th centuryFragment of an Icon of the Crucifixion with Mary Magdalene and the Virgin MaryByzantium, Byzantine period, 14th century, 1300sPortable Triptych IconByzantium, Russia, Moscow?, Byzantine period, 17th century, 1600sIcon of the Mother of God and Infant Christ (Virgin Eleousa)Republic of Venice, Kingdom of Candia, Candia (Heraklion, Crete, Greece) or Byzantine Empire, Constantinople (Istanbul, Turkey), c. 1425–50Icon of the New Testament TrinityByzantium, Constantinople, c. 1450Pendant Icon of Our Lady of KazanRussia, 1915Icon with the DeesisByzantine, mid-900sPanel from a Cover for an Icon of the VirginByzantine, ca. 1100Icon with Christ PantokratorByzantine, 11th–12th centuryPendant Brooch with Cameo of Enthroned Virgin and Child and Christ PantokratorByzantine, late 1000s–1100s (cameo); 1100s–1300s (mount)Icon of the Virgin and Child, Hodegetria variantByzantine or Crusader, 13th century

Numbers

Eastern Orthodox Christians

c. 200–300 million (estimates vary)^[10]

No single recent count covers Eastern Orthodoxy alone. Britannica gives more than 200 million; the WCC's self-reported figure is 300 million. Pew's 260 million (2010) covers Orthodoxy as a whole, including Oriental Orthodox, so is not used.

Orthodox Christians in Russia

More than 100 million (Pew, 2017)^[76]

An estimated 39 million in 1970, under Soviet rule. Only 6% of Russia's Orthodox adults told Pew they attend church weekly.

Monks on Mount Athos

Some 1,400 (UNESCO)^[72]

Britannica says more than 1,000 monks in 20 monasteries.

National censuses

Source: Australian Bureau of Statistics, Census of Population and Housing 2021, 'Religious affiliation in Australia' (Table 4), CC BY 4.0. Adapted from Statistics Canada, Table 98-10-0342-01 Religion by visible minority and generation status: Canada, provinces and territories, census metropolitan areas and census agglomerations with parts, released 2022-10-26. This does not constitute an endorsement by Statistics Canada of this product. Source: Stats NZ, 2018 Census, licensed by Stats NZ for re-use under the Creative Commons Attribution 4.0 International licence.

Common misconceptions

Glossary

Autocephaly · αὐτοκεφαλία

Literally self-headedness: the status of a church that governs itself and elects its own primate, while remaining in communion with the other Orthodox churches.^[81]

Tomos · τόμος

A formal decree of a patriarch and synod, such as the charter granting autocephaly to a church: Greece received one in 1850 and Ukraine in 2019.^[82]

Ecumenical Patriarch

Title of the archbishop of Constantinople, who holds the first place of honour among the bishops of the Orthodox churches.^[83]

Phanar

The Fener district of Istanbul, where the Ecumenical Patriarchate has had its seat since Ottoman times.^[84]

Millet

In the Ottoman Empire, a religious community with its own leaders; the Orthodox formed the Rum (Roman) millet under the Ecumenical Patriarch.^[27]

Hesychasm · ἡσυχασμός

From hēsychia, 'quiet': a tradition of monastic prayer centred on the Jesus Prayer, defended by Gregory Palamas and endorsed by councils in the 14th century.^{[44, 58]}

Iconostasis

The screen of icons separating the sanctuary from the nave, with the Royal Doors at its centre, Christ on their right and the Theotokos on their left.^[85]

Filioque

Latin for 'and from the Son': words added to the creed in the West, saying that the Spirit comes forth from both Father and Son. The Orthodox reject the addition.^[41]

Old Believers

Russian Orthodox who refused Patriarch Nikon's 17th-century liturgical reforms, such as crossing oneself with three fingers instead of two, and formed separate communities.^[29]

Pascha · Πάσχα

The Orthodox name for Easter, taken from the Greek and Latin word for Passover.^[86]