The essence of gnosticism as I’ve always understood it, Kolo, is not that they posited man as a spiritual being, but that they insisted that God would not become an earthly being. Thus, John’s words about God becoming flesh and dwelling among us. Also, John’s words about those denying that Jesus (the Christ) has come in the flesh.
Therefore, to suggest that the original human lived in a spiritual realm that we no longer inhabit is to ignore the angel with the flaming sword guarding Eden.
To suggest that a human is both spirit and body is to ignore the entire testimony of the bible, but especially of Romans 7. Such a belief is not gnostic; it is thoroughly Christian.
No, because that is precisely what Judaism believes. The difference between Gnostcis and Jews is more than just a label. Gnostcis believe that those souls living in the flesh are souls that have sinned and were cast out of their natural spiritual existence and placed into a fleshy "dungeon." Judaism doesn't believe that at all. Judaism completely rejects the idea of the original sin having anything to do with any change in human nature.
If Gnostics were right, then man and angels were both noëtic spirits. The way Alamo Girl describes Adam, originally existing only as a spirit, makes him an angel who was given dominion over earth.
I suppose one could find biblical support for this, given that Adam is referred to as the "son of God," a title also given to angels, but it doesn't epxlain why were Adam and Eve (a female angel???) given bodily "prisons" for their sin, and the [other] fallen angels were not.