Wikipedia
Cerinthus (; fl. c. 100 CE) was a gnostic and to some, an early Christian, who was prominent as a heresiarch in the view of the early Church Fathers. Contrary to proto-orthodox Christianity, used the Gospel of Cerinthus, and denied that the Supreme God made the physical world. In Cerinthus' interpretation, the Christ came to Jesus at baptism, guided him in his ministry, but left him at the crucifixion.
He taught that Jesus would establish a thousand-year reign of sensuous pleasure after the Second Coming but before the General Resurrection, a view that was declared heretical by the Council of Nicaea. Cerinthus used a version of the gospel of Matthew as scripture.
Cerinthus taught at a time when Christianity's relation to Judaism and to Greek philosophy had not yet been clearly defined. In his association with the Jewish law and his modest assessment of Jesus, he was similar to the Ebionites and to other Jewish Christians. In defining the world's creator as the demiurge, he emulated Platonic philosophy and anticipated the Gnostics.
Early Christian tradition describes Cerinthus as a contemporary to and opponent of John the Evangelist, who may have written the First Epistle of John and the Second Epistle of John to warn the less mature in faith and doctrine about the changes Cerinthus was making to the original gospel. All that is known about Cerinthus comes from the writing of his theological opponents.