The Church of the East

Where it came from

The Church of the East developed in Mesopotamia and Persia, beyond the Roman Empire’s eastern frontier. Its traditions connect its origins with Thomas, Addai, and Mari; written evidence documents its early growth. This setting produced a Christian history that was neither Roman Catholic nor Byzantine Orthodox.

Medieval missions extended into India, Central Asia, and China. The tradition’s history includes scholarship and cultural exchange, as well as persecution and displacement. Syriac, a form of Aramaic, became its principal language of worship and theological expression. Its communities today preserve part of this wider history of Christianity across Asia.

What it emphasizes

The Assyrian Church of the East confesses the Trinity and Jesus Christ as truly God and truly human, united in one person. Its theological vocabulary developed differently from Greek and Latin Christian language. Older books often call it “Nestorian,” associating it with controversies about Nestorius, a fifth-century bishop. That label can misrepresent its own confession and is rejected by the church.

In a 1994 joint declaration, Catholic and Assyrian leaders affirmed a shared confession of Christ’s full divinity and humanity. They recognized that different inherited expressions need not imply two opposing faiths about Jesus. They also acknowledged that complete church unity had not yet been achieved. The declaration below sets out the agreement in the churches’ own words.

Worship and organization

The Holy Qurbana, meaning Holy Offering, is the central Eucharistic service. The liturgy associated with Addai and Mari is especially important. Worship joins biblical readings, prayer, and Communion; the church understands Christ to be truly present in the bread and wine.

Bishops, priests, and deacons serve the community. A catholicos-patriarch is its presiding bishop, working with the bishops’ synod, or council. Sacramental life includes infant baptism as well as the baptism of adult converts. Compare Christian approaches to baptism.

Differences within the family

The historic tradition has more than one modern institutional heir. The Assyrian Church of the East and Ancient Church of the East are distinct bodies; Chaldean Catholic communities share East Syriac heritage while belonging to the Catholic communion. Historical relationships do not make these interchangeable names.

Assyrian cultural identity and the preservation of Syriac are important, but this tradition’s past crosses many peoples. A local congregation can explain its own affiliation, service language, and expectations for visitors. It should not be confused with the separate Syriac Orthodox tradition within Oriental Orthodoxy.