410 (independence) – 486 (Synod of Seleucia) – 489–507 (school of Nisibis) – 585 (synod)

The Church of the East ("Nestorian") in Persia: formation and establishment

The Christians of Persia were subjects of a power hostile to Rome. From 410 they organized themselves into an independent church headed by a patriarch at Ctesiphon.

After the condemnation of Nestorius, Antiochene theologians fled to Persia and reinforced a "two natures" Christology there. In 489 Zeno closed the theological school of Edessa. Its teachers, led by Barsauma, transferred it to Nisibis. There Narsai ("the Harp of the Holy Spirit") headed the school until his death in 507, with the formula "two natures, two hypostases, one manifestation."

The Synod of Seleucia in 486 formally adopted a Christology of "two natures, united unmingled and unchanged in a single person." The synod of 585 recognized only Nicaea and Constantinople I as the measure of truth, rejecting Ephesus and Chalcedon.

In the early 7th century Babai the Great ("the creator of Nestorian dogmatics") completed the formulation: "two natures, two hypostases (qnome), one person (parsopa) of sonship." It included the doctrine of two wills in Christ.