Docetism is the false belief that Christ only appeared to be human, but is not truly and fully human as we are. The term comes from the Greek verb dokeō which means “to think, to seem, or to appear.” A dokēsis is a phantom or apparition which is not human. But why would anyone believe that Jesus is not truly human? The motivation for docetism is rooted in a gnostic worldview which views the material world as intrinsically evil and impure. Hence, the argument goes, if Jesus is human as we are now, then he would be impure and not a true teacher from God. If matter is evil, then God could not become incarnate. It was also believed by gnostics that Jesus was an aeon who emanated from God and therefore could not be human.
After the Judaizers in Galatians and the hyper-preterism of Hymenaeus and Philetus (2 Tim 2:17-18), docetism was the third major heresy that the early church had to deal with. This is why John warns his readers against false teachers who denied the incarnation and humanity of Christ: “For many deceivers have gone out into the world, those who do not confess the coming of Jesus Christ in the flesh. Such a one is the deceiver and the antichrist” (2 John 1:7). He also wrote, “By this you know the Spirit of God: every spirit that confesses that Jesus Christ has come in the flesh is from God” (1 John 4:2). While there are not many full-blooded docetists around today, a form of docetism is found in the teachings of the Jehovah’s Witnesses who deny the bodily resurrection of Christ. Instead, they believe the resurrection of Christ was his reverting back to being the archangel Michael and that Jesus’ physical body no longer exists since it has dissolved into gas. But the Bible teaches that Jesus Christ is fully human now after his resurrection and not just before (Luke 24:39; John 2:19-21; 20:27; Acts 17:31; 1 Tim 2:5).
A common misconception many Christians have is that Jesus’ resurrection body is no longer a fleshly body of skin, bones, and blood (Luke 24:39). This is due in part to a misinterpretation of 1 Corinthians 15:44-45: “It is sown a natural body; it is raised a spiritual body. If there is a natural body, there is also a spiritual body. Thus it is written, ‘The first man Adam became a living being’; the last Adam became a life-giving spirit.” But “spiritual” does not mean non-physical, but incorruptible. It is a metaphor expressing incorruptibility and that which does not perish as seen by the use of synonymous terms in verses 50-54. Christ became a “spirit” in the sense that he became an incorruptible person as a result of his resurrection. The Greek word for “natural” here is psuchikos which is related to the word psuche or “soul” while “spiritual” is the word pneumatikos which is related to the word pneuma or “spirit.” Therefore, if “spirit” here means non-physical because it is derived from pneuma, then “natural” would also be non-physical because it is derived from psuche. As the “soulish” or “natural” body is physical, the “spiritual” one is as well. Two other related errors are monophysitism and monotheletism (the beliefs that Christ only possesses one nature and one will respectively) which are in danger of falling into docetism by denying that Christ has a human nature and a human will distinct from his divine nature and divine will.