Did Judas the traitor really write his own gospel? This one is really good fodder for conspiracy theorists. But don’t go looking for the “real truth” in this document just yet.
The “Gospel of Judas” is written in Coptic, and the earliest copy dates from about the third century. When it was found, the news media and popular books portrayed it as a new discovery, but this false gospel was known all the way back in the days of Irenaeus in the second century.
Irenaeus mentioned the Gospel of Judas in his work Against Heresies and called it invented history, written by a Gnostic group. The Gnostics believed matter was evil, including the human body, and so part of their “salvation” was to be liberated from the body. So in the Gospel of Judas they make Judas into a hero who comes from another planet, and he is made a hero because he arranges for Jesus to be killed and thus “liberates” Him from that evil earthly body! Needless to say, this is a total reversal of the account of the canonical Gospels and is right along the lines of Gnostic thought. It is just another example of the remaking of “Jesus” by the Gnostics into their own imaginary character.
The same lack of reliable history is true of the other “ lost gospels,” which have been found in Egypt and other sites, such as the “Gospel of Mary,” where “Jesus” was deduced by some to have been married to Mary Magdalene, or the Apocryphon of John, where the Gnostic Jesus was supposedly explaining the hidden meanings of some of the Old Testament accounts to his disciple John. Grant and Freedman comment on these and other Gnostic fragments discovered: “We therefore have, in Till’s edition, fifth century Coptic versions of three Gnostic gospels or semi-gospels which go back to the second and third centuries of our era. There is no reason to suppose that any of them contains the faintest reminiscence of authentic words of Jesus.” Significantly, these authors seem to be trying to give an unbiased, even sometimes favorable treatment of these documents; yet they honestly admit their shortcomings.
I think we can see that the Gnostic “gospels” are in fact the legendary works the critics are looking for. And the real truth can be found in the earliest and most reliable sources, namely our four canonical gospels.
 Price, Searching for the Original Bible, 2007, 187-188.