Not an Old Testament reference, but a Gnostic belief. 1 John addresses Gnosticism by refuting some of its claims such as Jesus only appearing to be human. While John doesn't reference the Demiurge, the concept goes hand in hand with this Gnostic teaching that Jesus was a pure spiritual being. Gnostics considered material things evil, so Jesus coming in the flesh and a benevolent creator God did not fit their worldview.