@ChenHuailun here. I'm adding a supplementary thread before…

The Church of the East traces its origins to the christological position of the School of Antioch, which held that the human and divine and human essences (ουσία) of Christ were united in a single prosopon (πρόσωπον). ~ahc #jingjiao 2/

This ran against the position of the School of Alexandria, which held that the two essences of Christ were united in a single hypostasis (ὑπόστασις). In general terms, hypostasis is more inherent than prosopon. ~ahc #jingjiao 3/

One implication of the Antiochene rejection of the hypostatic union is that Mary could not accurately be called the Theotokos, or God-bearer. Instead, she is the Christotokos, the Christ-bearer. ~ahc #jingjiao 4/

These Christological debates were further complicated by Syriac terms such as 'kyana' (ܟܝܢܐ), associated with 'ousia' but later translated to 'hypostasis' by Syrian Orthodox; and 'qnoma ' (ܩܢܘܡܐ), sometimes contentiously translated as 'hypostasis' or 'person.' ~ahc #jingjiao 5/

The eponymous Nestorius adhered to the Antiochene school, but the distinct credal identity of the Church of the East emerged from the theological School of Edessa which transmitted the teachings of Theodore of Mopsuestia, of whom Nestorius was a student. ~ahc #jingjiao 6/

Though Nestorius was condemned at the Council of Ephesus (431), the School of Edessa did not close until 489, and Theodore of Mopsuestia was eventually anathematised in at the Council of Constantinople (553) ~ahc #jingjiao 7/

With persecution in the Byzantine empire, inheritors of the School of Edessa grew in the Sasanian empire. The Zoroastrian priest Kerdir mentions the presence of Christians in the empire as early as the 3rd cent. ~ahc #jingjiao 8/

Under the Sasanians, Christians suffered periodic religious violence, as attested by the Acts of the Persian Martyrs. ~ahc #jingjiao 9/

But it wasn't until the 5th cent when the Persian church distinguished itself organisationally at the 410 synod of Seleucia-Ctesiphon, which centred the hierarchy of the Church of the East on the bishop of Seleucia-Ctesiphon, who bore the title of 'catholicos.' ~ahc #jingjiao 10/

Now distinct, Church of the East first encountered their Muslim conquerors. The catholicos Ishoʿyahb II (r. 628–45) allegedly saw the Prophet Muhammad in person, and later negotiated a treaty of protection for Christians with the Rashidun caliph ʿUmar. ~ahc #jingjiao /11

Under the Islamic caliphates, East Syrian (Nestorian) Christians appear in the history primarily as apologetic writers, translators, and physicians. ~ahc #jingjiao /12

Syriac Christians played a central role in Graeco-Arabic translation movement, the most famous perhaps being the 'circle' of al-Kindi.

Al-Farabi also studied Aristotelian logic under the East Syrian Christians Yuhanna ibn Haylan and Abu Bishr Matta ibn Yunus. ~ahc #jingjiao /13

Perhaps the most well-known East Syrian Christian of this period was the physician Hunayn ibn Ishaq, who translated the works of Galen and headed the Graeco-Arabic translation centre at the House of Wisdom (Bayt al-Ḥikma) in Baghdad. ~ahc #jingjiao /14

Significantly, there is a noticeable lack of martyr literature in the Church of the East under Islamic rule. East Syrian Christians may not have experienced the same levels of violence as their other Christian counterparts. ~ahc #jingjiao /15