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Council of Chalcedon: Christ fully God and fully human
October 451· Council, creed or writing· Church, doctrine & the world
Historical recordConfirmed by archaeology, outside sources or contemporary records.
The 451 council that defined Jesus Christ as one person in two natures, fully God and fully human.
See it on the Bible & Christianity map →What it is
Emperor Marcian called about 500 bishops (estimates vary) to Chalcedon, across the Bosporus from Constantinople. The issue: how Christ's divinity and humanity fit together. Nestorius had seemed to split Christ in two; the monk Eutyches had merged the human into the divine. A letter from Pope Leo I, the 'Tome', was hailed: 'Peter has spoken through Leo.' The council defined Christ as one person 'in two natures, without confusion, without change, without division, without separation.'
Why it matters
Its definition is accepted by Catholic, Eastern Orthodox and most Protestant churches, but it caused a lasting split with the Oriental Orthodox churches.
Sources and history
Unusually full minutes of its sessions survive in Greek and Latin, making it one of the best-documented meetings of the ancient world.
Questions and debates
Its Canon 28, ranking Constantinople's bishop next to Rome's with 'equal privileges', was rejected by Pope Leo; whether it was valid stayed disputed between Rome and the East for centuries.
Inside this (1)
Connections (3)
▸Mary, mother of Jesus was reaffirmed as 'God-bearer' by Council of Chalcedon: Christ fully God and fully humanHistorical record
The connection
The Council of Ephesus (431) called Mary 'Theotokos', God-bearer, against Nestorius, who preferred 'Christ-bearer'. The point was about Jesus: if he is one person who is truly God, his mother bore God. Chalcedon repeated the title in its definition, saying Christ was 'born of the Virgin Mary, the God-bearer, as regards his humanity'.
When and where
Ephesus (western Turkey), 431, led by Cyril of Alexandria; restated at Chalcedon, October 451.
Historical evidence
The Chalcedonian Definition, preserved in the council's surviving minutes, uses the word 'Theotokos'.
Questions and debates
Many Protestants accept the title in principle but rarely use it. The Assyrian Church of the East historically rejected it; a 1994 declaration with Rome found common ground.
▸Council of Chalcedon: Christ fully God and fully human defined the two natures of Jesus of NazarethHistorical record
The connection
Chalcedon defined Jesus Christ as one person 'acknowledged in two natures, without confusion, without change, without division, without separation': truly God and truly human, of one being with the Father in divinity and with us in humanity. It rejected both Nestorius (two persons) and Eutyches (the human absorbed into the divine).
When and where
Chalcedon (now Kadıköy, Istanbul), October 451, under Emperor Marcian and drawing on Pope Leo I's Tome.
Historical evidence
The definition survives in the council's minutes. Historians can document it; its claims about who Jesus is rest on faith.
Questions and debates
Whether Greek terms like 'nature' and 'person' fit the Gospel portrait is debated; Oriental Orthodox prefer 'one incarnate nature' language for the same Christ.
▸Oriental Orthodox churches (Coptic, Armenian, Ethiopian, Syriac) rejected the definition of Council of Chalcedon: Christ fully God and fully humanHistorical record
The connection
Many Christians in Egypt, Syria and Armenia held to Cyril of Alexandria's phrase 'one incarnate nature of God the Word'. To them, Chalcedon's 'in two natures' leaned toward Nestorius, and its removal of Alexandria's bishop Dioscorus felt like an insult. Imperial attempts at compromise, like the Henotikon (482), failed, and separate churches formed.
When and where
Chalcedon (451), then Alexandria and Antioch in the following decades; Armenian councils at Dvin (506 and 554) formally rejected Chalcedon.
Historical evidence
Writings of the leading anti-Chalcedonian theologian, Severus of Antioch (died 538), and later church chronicles document the split.
Questions and debates
Modern dialogues, including Pope Paul VI with Coptic Pope Shenouda III (1973), found both sides hold the same faith in different words; full communion is not restored.