Article by Adriel Sanchez (Original source here)
Because the incarnation is so marvelously mysterious, there were groups in the early church that sought to explain its message in ways that undermined it. Here are three false teachings about Jesus that the early church had to reject:
1. Jesus only appeared to be human (Docetism).
Early in the church, there were those who argued that the incarnate God only appeared to be human. After all, how could God possibly take human flesh to himself? The idea seemed absurd to them because they couldn’t fathom God being hungry, tired, or in pain.
Therefore, they denied that Jesus had any human experiences. This teaching was known as Docetism. It undermines Christianity, because if Jesus didn’t really embrace our suffering in the incarnation, then he didn’t bear our sin and cannot relate to our pain.
2. Jesus was subordinate to his Father in power and glory (Arianism).
Unlike the Docetists, another group believed Jesus was truly a man, but not equal with God the Father in power and glory. This group attacked Jesus’s divine status. After all, how could God himself have such immediate contact with mankind? In order to deal with this perceived problem, this group attempted to strip Jesus of his eternal nature, and they were known as Arians. Arianism undermines the Bible’s teaching on God being one in essence and three in persons, because only God himself could rescue people from their sin.
3. Jesus’ humanity and divinity existed separately from each other (Nestorianism).
A third group tried to explain the mystery of the incarnation by splitting apart the divinity and humanity of Jesus. After all, how could divinity and humanity exist so perfectly in one Person? This group separated the divine actions of Jesus (such as healing) from his human experiences (suffering) and taught that there were two subjects in the incarnation instead of one divine Person. This teaching is known as Nestorianism. It undermines the believer’s hope in Christ, because if the divine Second Person of the Trinity didn’t truly unite humanity to himself, there’s no hope that we can be made “partakers of the divine nature” (2 Pet.1:4).
These three explanations of the incarnation were rejected by the Christian church. In the final analysis, none of them went far enough in their description of how marvelous the Incarnation was.
The eternal Son of God took to himself true humanity and bore our pain in that humanity to redeem us. The early church father Gregory of Nazianzus explained the importance of rightly understanding the incarnation with the famous dictum taken from his letter “To Cledonius the Priest Against Apollinaris”:
“For that which he [Jesus] has not assumed he has not healed; but that which is united to his Godhead is also saved.” He continued, “If only half Adam fell, then that which Christ assumes and saves may be half also; but if the whole of his nature fell, it must be united to the whole nature of Him that was begotten, and so be saved as a whole. (Nicene and Post Nicene Fathers, Vol 2, #7, p. 648, at www.ccel.org )
Thankfully, God shared in the whole of our fallen humanity so that through his death he might make us partakers of the life found only in him.