Assyrian Church of the East

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Theology
Hesychasm - Icon Apophaticism - Filioque clause Miaphysitism - Monophysitism Nestorianism - Theosis - Theoria Phronema - Philokalia Praxis - Theotokos Hypostasis - Ousia Essence - Energies distinction Metousiosis

The Holy Apostolic Catholic Assyrian Church of the East[1][2] (in Assyrian Neo-Aramaic ܥܕܬܐ ܩܕܝܫܬܐ ܘܫܠܝܚܝܬܐ ܩܬܘܠܝܩܝ ܕܡܕܢܚܐ ܕܐܬܘܪ̈ܝܐ, ‘Ittā Qaddishtā wa-Shlikhāitā Qattoliqi d-Madnĕkhā d-Āshurāyē, in Arabic كنيسة المشرق الآشورية الرسولية الكاثوليكية المقدّسة ), or simply Assyrian Church of the East presently presided over by H.H. Mar Dinkha IV, is a Christian particular church and one of the oldest. It traces its origins to the See of Seleucia-Ctesiphon, which tradition holds was founded by Saint Thomas the Apostle as well as Saint Mari and Saint Addai as asserted in the Doctrine of Addai.

It has also been referred to, inaccurately, by a number of other names. These include the Syrian Church, the Persian Church, and the Assyrian Orthodox Church, which has led some to mistakenly believe that it is a body of the Oriental Orthodox community. The church itself does not use the word "Orthodox" in any of its service books or in any of its official correspondence, nor does it use any word which can be translated as "correct faith" or "correct doctrine", the rough translation of the word Orthodox. In India, it is known as the Chaldean Syrian Church. In the West it is often known as the Nestorian Church although the church itself considers the term pejorative, as it never subscribed to Nestorianism. The church declares that no other church has suffered as many martyrdoms as the Assyrian Church of the East.[3]

The Assyrian Church teaches that it is the original Christian church founded by the Apostle St. Thomas (Tooma Shlikha) himself dating back to 33 A.D. in what was once Parthia; eastern Iraq and Iran. Geographically it stretched in the medieval period to China and India: a monument found in Xi'an (Hsi-an), the Tang-period capital of China (originally Chang'an), in Chinese and Assyrian Neo-Aramaic described the activities of the church in the 7th and 8th century, while half a millennium later a Chinese monk went from Beijing to Paris and Rome to call for an alliance with the Mongols against the Mamelukes. Prior to the Portuguese arrival in India in 1498, it provided "East Syrian" bishops to the Saint Thomas Christians. Patriarch Timothy I (727–823) wrote of the large Christian community in Tibet.

The founders of Assyrian theology are Diodorus of Tarsus and Theodore of Mopsuestia, who taught at Antioch. The normative Christology of the Assyrian church was written by Babai the Great (551–628) and is clearly distinct from the accusations directed toward Nestorius: his main christological work is called the 'Book of the Union', and in it Babai teaches that the two qnome (essences, or hypostases) are unmingled but everlastingly united in the one parsopa (personality) of Christ.