Fully God, Fully Human

Christians do not believe that Jesus Christ was just a great prophet, moral teacher, or an exalted human being. We believe he was the “incarnate” Son of God. The incarnation refers to when Jesus became human and “took on flesh.” Christians believe that Jesus is one person, but he has two natures. He has a divine nature, and he has a human nature.

In his divine nature, Jesus is co-eternal and co-equal with God the Father and the Holy Spirit. In his human nature, he was born of the Virgin Mary and fully shared in our human experience. We find the basis for these beliefs in various biblical passages like John 1:1 and 14, which state, “In the beginning was the Word, and the Word was with God, and the Word was God... And the Word became flesh and dwelt among us.”

This dual nature of Christ is crucial for orthodox Christianity because it allows for Jesus to be the perfect mediator between God and humanity. As fully divine, He possesses the power to save us from sin and reconcile us to God. As fully human, He understands our struggles and can sympathize with our weaknesses (Hebrews 4:15). This paradoxical understanding of Jesus’ nature has been the subject of intense theological debates and has given rise to various heretical beliefs throughout history.

One of the earliest and most significant decisions in relation to the orthodox view of Jesus’ nature arose during the Arian controversy in the 4th century. Arius, a presbyter from Alexandria, propagated the belief that Jesus, as the Son of God, was a created being and not co-eternal with the Father. This belief came to be known as Arianism.

Because the church was divided, the emperor Constantine called for the first ecumenical council at Nicaea in 325 AD. The council’s primary objective was to address the Arian controversy and formulate a creed that accurately expressed proper Christian belief. The Creed of Nicaea, which was adopted at the council and would later develop into the Nicene Creed (381), firmly asserted the eternal divinity of Jesus Christ and rejected Arianism. It affirms that Jesus is “God of God, Light of Light, true God of true God, begotten, not made, of one essence with the Father.”

While the Council of Nicaea officially resolved the Arian controversy, it did not put an end to debates surrounding the nature of Christ. In fact, at one point in the mid-300s, there probably were still more Arian Christians than Nicene ones. Those debates were more decisively ended at the Council of Constantinople in 381, after Christianity had become the exclusive and official religion of the Roman Empire.

In the 400s, controversies over the nature of Christ centered on understanding how Jesus’ divine and human natures were united in his one person. The Council of Chalcedon in 451 AD sought to address these controversies. It formulated the Chalcedonian Definition, which is considered the standard orthodox Christological position. According to this definition, Jesus Christ is acknowledged to be “one and the same Son, the same perfect in Godhead and also perfect in manhood; truly God and truly man.”

The Chalcedonian Definition rejected two major opposing positions:

1. Nestorianism, which held that there were two separate persons in Jesus – one divine and one human.
2. Eutychianism or Monophysitism, which claimed that Jesus' divinity was more or less all that counted because it was so much more than his humanity, resulting in a single divine-human nature.

Despite the decisions that took place at Nicaea and Chalcedon, old heretical views reemerge on a popular level from time to time. These popular versions of heresies challenge the orthodox understanding of Jesus' nature. Here are some old heresies that still show up here and there:

1. Adoptionism: This view suggests that Jesus was merely a human who was “adopted” or “chosen” by God to become the Messiah. In this perspective, Jesus did not possess a divine nature inherently, but rather received divine attributes later in life.
2. Docetism: Docetism denies the true humanity of Jesus, asserting that His physical body was an illusion. According to this belief, Jesus only appeared to be human, but in reality, He was purely divine. Whenever someone doesn’t really consider Jesus to be human, this heresy peeks out.
3. Arianism: Some contemporary groups still advocate for Arian-like beliefs, claiming that Jesus was a created being or a lesser deity compared to the Father.

The orthodox Christian position maintains that Jesus Christ is fully divine and fully human. Any view that either ignores his humanity or underplays his divinity is falling into the same traps of long ago.