This question can get technical very quickly, so I recommend easing into the subject this way:
1. Two articles, with pictures, from Tom Verenna
2. Move on to the brief post from Paul Barford
3. Dive into the deep end with the scholars at Evangelical Textual Criticism (read the comments section)
UPDATE:
4. Put on your protective gear and read this from Francis Watson
Funny how some people (scholars?) want to major on the minors, really obtuse! As you have well quoted and shown, this is simply “Gnostic”! Time to move on, and leave the “scholars” to their toys.
For scholars of early Christianity and Coptic, Gnosticism is a major area. It’s interest to Nicene orthodox Christians is another matter. Personally the Nag Hammadi books always make me want to hurl them across the room after a while.
Agreed about real scholarship! Sadly, too often there is a real lack in Judeo-Christian authority there; and one does not need to be a “Christian” to engage.