Well, to my knowledge it was at the Council of Nicea that the New Testament was formed. And I don't know where you got the idea that I tried to tell you that the Gnostic library and the New Testament are related, but to clarify, those documents were candidates for the current canonical New Testament. Pretty much all of them were discarded for obvious reasons you stated (They are, in fact, Gnostic writings after all). Gnosticism at that point was a form of heresy, and it was father Athanasius (A member at the council of Nicea) who fought such heresy across the known world. Look up Iraneus if you are still unclear.