two natures of Christ

Christ, detail from the late Byzantine Deesis mosaicChrist, detail from the late Byzantine Deesis mosaic, south gallery, Hagia Sophia, Istanbul, c. 1300.

two natures of Christ, in Christianity, the doctrine stating that Jesus, through the Incarnation, became fully human and fully divine and that these natures cannot be separated. The idea that “Jesus Christ is true God and true man” is also referred to as the hypostatic union and is a central tenet of Orthodox Christianity. Indeed, the Christian doctrine of salvation depends on the belief that Christ had to become fully human to share his full divinity with humanity.

Christ is often referred to as “the Word” (see logos) in Scripture, a term that refers to divine order, illumination, and the source of life and creation. The Gospel According to John states that Jesus is the Word incarnate who reveals God to humanity; the other Gospels and New Testament writings also address this idea. However, the full and technical doctrine of the two natures of Christ was arrived at over time, often with much controversy and debate.

In the first centuries following Christ’s death, the church was forced to develop a succinct theology regarding the two natures of Christ in order to address and quell a number of divergent belief systems it deemed heresies. Gnostic Docetists, for example, believed that Christ was not truly human and did not truly suffer; Docetism was attacked by numerous opponents of gnosticism, particularly Bishop Ignatius of Antioch in the 2nd century. Another early 2nd century heresy was Monarchianism, which stated that God the Father was the sole deity and that Jesus, while considered the Redeemer, was merely a mortal endowed with divine wisdom. In 341 the Council of Antioch declared that Jesus was the Son of God by nature rather than by adoption, refuting Monarchianism.

Another significant challenge came from Bishop Arius of Alexandria, who emphasized the oneness of God. He stated that the essence (ousia) of God the Son was different from that of God the Father and that Christ could not be the same as the God of creation. He also posited that the Son came from the Father and had a beginning. In 325 the First Council of Nicaea sought to refute Arius, declaring that Christ was “begotten, not made, of the same substance as the Father.” The council used the Greek word homoousios, “of one substance,” rather than homoiousios “of similar substance.”

As a reaction against Arianism, Bishop Apollinarus the Younger stressed that Christ was divine nature housed in a human body without a human soul. In 381 the First Council of Constantinople rejected Apollinarianism as being insufficient to describe Christ as God incarnate and adopted the Nicene Creed.

The rise of Nestorianism necessitated further doctrinal uniformity, especially in relation to the personhood (hypostasis) of Christ. In 428 Bishop Nestorius of Constantinople objected to the use of the word Theotokos, “God-bearer,” to refer to the Virgin Mary. Nestorius’s refusal to style Mary as mother of God seemed to deny the unity of the God-man. In 431 the Second Council of Ephesus affirmed “that the Word, uniting to himself in his person the flesh animated by a rational soul, became man.” Nestorianism was also condemned at the Council of Chalcedon in 451.

The Council of Chalcedon also addressed the ideas of Eutyches and the monophysites, who held that Christ’s nature was altogether divine and not human. The council refuted this belief in a single nature, affirming that Christ was “perfect in Godhead and also perfect in manhood; truly God and truly man…consubstantial with the Father…and consubstantial with us.”

Debates about the two natures of Christ continued after the Council of Chalcedon. In 482 the Byzantine patriarch Acacius attempted to reconcile differences with the monophysite sect, which insisted that Christ had only a single, divine nature. Acacius drew on the ideas of Christ’s divinity from the councils of Nicaea and Chalcedon but failed to acknowledge Christ’s humanity. While accepted by the Eastern church, Acacius’s teachings were declared unacceptable by the Roman Pope Felix III in 484, who excommunicated Acacius; the resultant Acacian Schism was not resolved until 519.

In 553 the Second Council of Constantinople further defined Christ as a unique, single person, a hypostasis, and one member of the Trinity. The 14 anathemas issued by the council further rejected Nestorianism by insisting yet again upon the hypostatic unity of the person of Christ in his two natures, divine and human.

Jennifer Murtoff