Why have Gnostic texts been rejected by Christianity while the book of John has been accepted as canon?
It’s my understanding that the gnostic gospels (from gnosis = to know) lean typically more toward self-enlightenment and the person as his own co-savior. The synoptic gospels and John, which all draw from each other successively, were found to be much more appealing to the masses. There’s also the factor that some of the gnostic gospels simply didn’t ring true and seemd canted toward a particular agenda.