In recent days much has been said about “lost books” of the Bible. The fact is, these “new” writings were known to the early Christians, but were rejected. They demonstrated a lack of credibility in a variety of ways.

The false teaching of these “other” gospels is evident even today. That they disagree with the writings of the apostles is proof enough they were not genuine. Even though some claimed to be written by an apostle, they were falsely attributed. (Peter, Thomas, and Judas were long dead before those accounts were written.)

A helpful explanation about how the Bible came to be is posted here.

Actually, there is a gospel testimony from each of these men:
Peter — “You are the Christ, the Son of the living God.” Matt. 16:16
Thomas — “My Lord and my God!” John 20:28
Judas — “I have sinned by betraying innocent blood.” Matt 27:3, 4

For an enlightening evaluation of the media claims concerning the Gospel of Judas, read this NY Times article