An ancient manuscript rediscovered after 1,700 years may shed new light on the relationship between Jesus and Judas, the disciple who betrayed him.

Rather than the traitor Judas is portrayed as in the New Testament, this document — the "Gospel of Judas" — indicates that he acted at the request of Jesus to help him shed his earthly body.

"Let a vigorous debate on the significance of this fascinating ancient text begin," the Rev. Donald Senior, president of the Catholic Theological Union of Chicago, said Thursday.

Senior expressed doubt that the new gospel will rival the New Testament, but allowed that opinions are likely to differ on it.

The text helps show the diversity of beliefs in early Christianity, added Marvin Meyer, professor of Bible studies at Chapman University in Orange, Calif.

Elaine Pagels, a professor of religion at Princeton University, commented that "the people who loved, circulated and wrote down these gospels did not think they were heretics."

The papyrus manuscript, probably written around 300 A.D. in Coptic script, is a copy of an earlier Greek manuscript, said Terry Garcia of the National Geographic Society, which made the manuscript public.

It was discovered in the desert in Egypt in the 1970s and has now been authenticated by carbon dating and studied and translated by biblical scholars, National Geographic announced.

Unlike the four gospels in the Bible, this text indicates that Judas betrayed Jesus at Jesus' request.

The text begins "the secret account of the revelation that Jesus spoke in conversation with Judas Iscariot."

The key passage comes when Jesus tells Judas "you will exceed all of them. For you will sacrifice the man that clothed me."

This indicates that Judas would help liberate the spiritual self by helping Jesus get rid of his physical flesh, the scholars said.

The manuscript was first mentioned in a treatise around 180 A.D. by a bishop, Irenaeus of Lyon, in what is now France. The bishop denounced the manuscript as differing from mainstream Christianity and said it produced a fictitious story.

There were several gospels in circulation at the time in addition to the four in the Bible. When those gospels were denounced, it was thought that believers hid them away.

The gospel of Judas was kept by a group called the Gnostics, who believed that the way to salvation was through secret knowledge given by Jesus to his inner circle.

National Geographic said the author of the gospel of Judas believed that Judas Iscariot alone understood the true significance of Jesus' teachings.