The heresy of Docetism is named for the transliteration of the Greek δοκεῖν/δόκησις, meaning “phantom” or “illusion.” The word refers to the 2nd Century AD teaching that Jesus only seemed to be human, and that his flesh was only an illusion. The earliest signs of Docetism appear in a pseudepigraphal work (a book purporting to be Scripture, but with an unknown author and falsely attributed to someone else), the Gospel of Peter.
Docetism was rejected as heresy at the Council of Nicaea (AD 325). A subset or subsidiary of Gnosticism, Docetism degrades the full two-fold nature of Christ.
Modern adherents include Muslims, whose religion teaches that the crucifixion was an illusion, and certain Christian liberals. Many practice a Neo-Docetism when they allegorize or make into a metaphor the life, death or resurrection of Christ. Jehovah’s Witnesses hold to Docetism, believing that the Resurrection of Christ did not include his earthly, physical body.