And Judas Iscariot who also betrayed him ..." With these words, St Mark ends his list of the chosen 12 apostles. It's the first mention of Judas, and it stamps him indelibly. Throughout the Christian centuries, red-haired, yellow-gowned Judas has been a synonym for traitor; a Judas- king signifying treachery towards one to whom you owe loyalty ....

Scholars have, however, been questioning his role, and asking why the Church for centuries laid such stress on it. That role has actually always been ambiguous, if only because the Gospels insist that Jesus knew that one of his apostles would betray him, "that the scriptures might be fulfilled". If so, then Judas may be seen almost as a scapegoat, the man forced by destiny to play this part. One may ask why it was necessary that one of the apostles should betray him since Christ's arrest, trial, crucifixion and resurrection could, one assume, have taken place without any act of treachery. Was Judas, one wonders, necessary to the authors of the Gospels principally for dramatic effect?

Among those who question the traditional Judas story are a Canadian scholar, Professor William Klossen of the Ecole Biblique in Jerusalem, and Hugh Maccoby, author of Judas Iscariot and the Myth of Jewish Evil.

Klassen bases his case first on the translation or, as he would have it, mistranslation, of the Greek verb varadidomi. This means simply to "hand over" rather than to "betray". The word is used 50 times in connection with the death of Jesus, and is, he says, translated 27 times as "hand over" where Judas is not mentioned, and 32 times as "betray" when used of Judas.

This certainly seems to indicate a degree of prejudice on the part of the translators, but I am not sure this evidence is as compelling as Klassen supposes. Is there really so much difference between the meanings "hand over" and "betray" in this context? If, for instance, in an account of the French Resistance, we were to read that someone "handed over" a Resistance fighter to the Gestapo, wouldn't we regard this as an act of betrayal?

But Klassen, though regarding Judas as an informer rather than a traitor, does at least offer a plausible explanation of his conduct. He suggests that Judas didn't realise that the Jewish priests, whom he guided to Gethsemane, were in turn going to hand Jesus over to the Romans for trial and execution. He is not, as I shall show, the first writer to have put forward this explanation, which has this merit: that it makes sense of Judas' subsequent behaviour. Even before the crucifixion, Judas returned his reward money - the infamous 30 pieces of silver - because, as Matthew has him say: "I have sinned in that I have betrayed innocent blood." Met with the cynical reply: "What is that to us?", Judas went out and hanged himself in remorse.

Klassen sees the demonisation of Judas gathering pace as the Christian sect moved away from its Jewish roots as a result of St Paul's mission to the Gentiles. Judas, then, in this Greek-speaking Church, became the stereotype of the treacherous Jew, rejecting and betraying Christ. Klassen traces the development of Judas' role from the earliest Gospel, Mark, to thefull-blown villainy presented in the last written Gospel, John.

There might of course be another explanation. If that gospel really was written by the Apostle John, "the disciple whom Jesus loved", or compiled by someone who had spoken with John, then it might even reflect a personal animus. There is no reason to suppose the 12 apostles liked each other. There are tensions and antipathies even in close-knit groups with a common interest and purpose - whether they are the Apostles or New Labour.

Hyam Maccoby goes further than Professor Klassen. In his opinion, the Judas story did not "spring from any actual event" but was "dictated by mythological necessity. In other religious myths, a deity who brings salvation by his violent death has to have an evil betrayer". Judas was therefore elected as the fall-guy. "The role, played on an individual level by Judas, is played also by the Jews as a whole." Making Judas guilty allowed the medieval Church to pretend neither Jesus nor the other apostles were Jewish.

This makes some sense, but Maccoby goes further. He tells us that "in historical fact, neither Judas nor the Jews betrayed Jesus. Jesus was a Jewish messiah figure who aspired to liberate the Jews from Roman oppression and inaugurate the kingdom of God on Earth." Unfortunately Maccoby's use of the words "in historical fact" is tendentious. There is very little "historical fact" available to us, once you discard the gospels as evidence of the historical Jesus....