Ecumenical council

An ecumenical council is a formal assembly of bishops convened to address doctrine, discipline, or church governance across Christianity. Different Christian traditions recognize different councils as ecumenical.

First Council of Nicaea: The 325 council that rejected Arian teaching and produced an early form of the Nicene Creed. Its formulation of Christ’s relation to the Father became a foundational conciliar decision.
Council of Nicaea (325): The assembly of bishops convened by Constantine in 325 to address the Arian controversy and other church matters. Its proceedings illustrate how imperial convocation brought bishops together for a common decision.
Council of Jerusalem: An early Christian gathering described in Acts that considered whether Gentile converts had to observe Jewish law. It is a scriptural precedent for resolving a dispute through collective deliberation.
Athanasius of Alexandria: A fourth-century bishop and theologian who defended the Nicene position against Arianism. His advocacy helped preserve the Nicene account of Christ amid fierce opposition.
Eastern Orthodox Church: A communion of autocephalous churches that shares Byzantine liturgy and recognizes the first seven ecumenical councils. Its accepted council list differs from Roman Catholic and many Protestant accounts.
Council of Constantinople I: The 381 council that reaffirmed Nicaea and expanded the creed’s teaching about the Holy Spirit. It established a fuller statement of the creed associated with ecumenical orthodoxy.
Nicene Creed: A Christian statement of faith originating in the fourth century and expanded at Constantinople in 381. Creeds gave councils concise language for expressing and testing doctrinal agreement.
Synod of Elvira: A regional gathering of bishops in Hispania, usually dated to the early fourth century, known for its disciplinary canons. Regional synods preceded the large imperial-era assemblies later recognized as ecumenical.
Cyril of Alexandria: A fifth-century patriarch of Alexandria who was a leading opponent of Nestorius. His arguments shaped the Christological dispute addressed at Ephesus.
Catholic Church: The church in communion with the bishop of Rome, which recognizes a broader series of ecumenical councils. Its recognition of later councils highlights the differing scope of ecumenical authority.

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