Nestorianism

The Christological heresy of Nestorianism takes it’s name from it’s founder, Nestorius, who rejected the ancient title of Theotokos (‘God-bearer’) for Mary, thus emphasizing distinction between divine and human aspects of the Incarnation. Nestorian Christology promoted the concept of a prosopic union of two natures (divine and human) in Jesus Christ or, in other words, the man Jesus is not identical with the Divine Son but is loosely united with the Son, who lives within Jesus in one hypostasis of two natures: human and divine.

Nestorius’ teachings brought him into conflict with other prominent church leaders -most notably Cyril of Alexandria – when he publicly challenged the long-used title of Theotokos (‘God-Bearer’) for Mary. He suggested that Jesus contained two persons (dyoprosopism) loosely joined and that Mary was the mother of His human nature only and thus the title of Christotokos (Christ-bearer) was more appropriate.   While claiming to believe in one Christ in two natures, his explanation described the union of two distinct persons: “He who was formed in the womb of Mary was not God himself, but God assumed him. Through him that bears I worship him who is born.”  Therefore, Mary did not give birth to the incarnate Word of God, but rather only to Jesus who was the temple or vessel of God. Nestorius further concluded that it was not God who suffered and died on the cross, but only the man Jesus.

Nestorius’ opponents found his teaching too close to the heresy of adoptionism – the idea that Christ had been born a man who had later been “adopted” as God’s son. Nestorius was especially criticized by Cyril, Patriarch of Alexandria, who argued that Nestorius’s teachings undermined the Incarnation.  Christianity had long used the title of Theotokos for Mary to underscore the fact that she gave birth to the person, Jesus Christ, who was both fully human and fully divine.  The title of Theotokos as well as the theology of the Incarnation could be found in wide-spread Christian prayers such as the Sub Tuum Praesidium, but had its roots in Scripture:

“But why am I so favored, that the mother of my Lord should come to me?” [Gospel of Luke 1:43]

“The virgin will conceive and bear (Greek=tikto) a son, and they will call him Immanuel”, (which means “God (Greek=Theos) with us”). [Gospel of Matthew 1:23]

Cyril of Alexandria wrote to Nestorius, asking him to further explain himself.  Cyril then shared this correspondence with Pope Celestine in Rome asking for the Pope’s decision. Pope Celestine condemned the teaching of Nestorius and commanded him to recant. Instead, Nestorius demanded an ecumenical council, believing it would rule in his favor.  Nestorius and his teachings were eventually condemned as heretical at the Council of Ephesus in 431, and again at the Council of Chalcedon in 451. The Council’s condemnation led to the Nestorian Schism as some supporters of Nestorius relocated to the Sasanian Empire, where they founded the Church of the East. During the period from 484 to 612, gradual development led to the creation of specific doctrinal views within the Church of the East.  The Syriac theologian Babai the Great (d. 628) would later begin using the specific Syriac term qnoma (ܩܢܘܡܐ) as a designation for dual (divine and human) substances within one prosopon (person or hypostasis) of Christ. Such views were officially adopted by the Church of the East at a council held in 612. It wasn’t until the 21st century, however, that the Assyrian Church of the East, which had historically been regarded as a Nestorian church, signed a fully orthodox joint declaration on Christology with the Catholic Church and rejected the heresy of Nestorianism.

Sources: 

• Papandrea, James L. (2016). The Earliest Christologies: Five Images of Christ in the Postapostolic Age. InterVarsity Press.
• Brock, Sebastian P. (1999). “The Christology of the Church of the East in the Synods of the Fifth to Early Seventh Centuries: Preliminary Considerations and Materials”. Doctrinal Diversity: Varieties of Early Christianity. New York and London: Garland Publishing.