Assyrian Church of the East

Assyrian Church of the East

The separation between Eastern Orthodoxy and the Assyrian Church of the East occurred in the fifth century, following the Council of Ephesus in 431. This division predates both the Chalcedonian schism of 451 and the later Great Schism with Rome. The dispute was fundamentally Christological, concerning how the unity of Christ’s divine and human realities is to be understood and confessed.

The Council of Ephesus affirmed that Christ is one person (hypostasis) and upheld the title Theotokos (“God-bearer”) for the Virgin Mary as a necessary safeguard of this unity. By confessing Mary as Theotokos, the Council protected the truth that the one born of her is none other than the eternal Son of God incarnate. Eastern Orthodoxy receives Ephesus as the Third Ecumenical Council and regards its Christological definitions as binding and irrevocable.

The Assyrian Church of the East rejected the Council of Ephesus and developed its theology largely outside the Roman-Byzantine sphere. Its Christological formulation emphasizes a distinction between Christ’s divine and human realities, often described as two qnōmē united in one parsopa. This terminology reflects a different theological and linguistic framework from that employed by the Greek-speaking Church.

This position has frequently been labeled “Nestorian” by its critics, a designation the Assyrian Church of the East itself rejects. While modern discussions sometimes emphasize linguistic misunderstanding, the enduring issue remains theological: the refusal to accept the Council of Ephesus and its confession of Christ as one hypostasis and of Mary as Theotokos.

For Eastern Orthodoxy, the rejection of Ephesus constitutes a decisive break in doctrinal continuity. Whether compounded by language or historical circumstance, the separation has persisted for over fifteen centuries, rooted in divergent Christological confessions and the authority of the Ecumenical Councils.