Ultimately Gnostic “Christians” (who wrote the Nag Hammadi texts) were Christians in name only. They spread false gospels. 

Plenty of people had various opinions who saw Jesus Christ or heard stories of Him, had their own opinions/ideas and expressed them. Gnosticism is form of religious relativism, where everyone had their own truths.

That’s why there were so many ecumenical councils early on; to refute the many heresies that were springing up. 

There is only one Truth. That Truth is contained within the Orthodox Church, handed down to the 12 Apostles by Christ himself, who is God incarnate.