'In all four Gospels Judas Iscariot is said to be the one who betrayed Jesus to the authorities, leading to his arrest. The four accounts differ on why Judas did the foul deed. There is no reason stated in Mark, although we are told that he received money for the act, so maybe it was out of greed (14:10–11). Matthew (26:14) states explicitly that Judas did it for the money. Luke, on the other hand, indicates that Judas did it because “Satan entered into him” (22:3). In other words, the devil made him do it. In John, Judas is himself called “a devil” (6:70–71), and so presumably he betrayed his master because he had an evil streak. (Jesus Interrupted, p. 45-46)
Bart Ehrman likes to set up “contradictions” of this sort. He says, one gospel shows different motives than another or gives a different reason for something or another. In this section, he applies this claim against Judas’ motives. On the face value this claim of discrepancy looks like valid argument. After all, different gospel writers are explicitly giving divergent reasons for Judas’ actions. The Christian response is predictable: both (all) accounts are correct. Sometimes multiple reasons lead to certain outcomes. Ehrman thinks this is invalid:
The literary conclusion is that as is the case with Jesus himself, so too with Judas. Every portrayal of him is different, and we do a disservice to the author of each account if we pretend that he is saying exactly what some other author is saying. If Matthew wants to say that greed is what drove Judas to do what he did, but Luke wants to insist that the Devil made him do it, it is not really fair to either author to argue that they mean the same thing. If that’s what we think, we have, in effect, taken what Matthew says, combined it with what Luke says, and created then a mega-Gospel (for which we might as well throw in Mark and John as well, for good measure)—a Gospel found nowhere in the New Testament but simply in our own heads, as we write a Gospel of our own to substitute for the Gospels of the New Testament. In my view as a literary and historical scholar, that is not the best way to treat the early accounts of Jesus’ (or Judas’s) life. (The Lost Gospel of Judas Iscariot, p. 33)
Heavy teaching! Ehrman is insistent that we not mix and match divergent accounts. It is curious then, when Ehrman recounts his conversion from Christianity that he gives similar divergent accounts:
“What I actually did learn at Princeton led me to change my mind about the Bible. I did not change my mind willingly—I went down kicking and screaming… it became clear to me over a long period of time that my former views of the Bible as the inerrant revelation from God were flat-out wrong. My choice was either to hold on to views that I had come to realize were in error or to follow where I believed the truth was leading me. In the end, it was no choice. If something was true, it was true; if not, not. (Jesus Interrupted, vii)
In Jesus Interrupted, it is crystal clear: problems with the New Testament led to Ehrman’s rejection of Christianity. It was these facts that led him “kicking and screaming” from the Church. Contrast this with Ehrman in God’s Problem:
“On the contrary, I left kicking and screaming, wanting desperately to hold on to the faith I had known since childhood and had come to know intimately from my teenaged years onward. But I came to a point where I could no longer believe. It’s a very long story, but the short version is this: I realized that I could no longer reconcile the claims of faith with the facts of life. In particular, I could no longer explain how there can be a good and all-powerful God actively involved with this world, given the state of things.” (God’s Problem, p. 3)
If we were to take Ehrman’s own methology, we would be forced to claim that one of these books was not written by Ehrman’s own hand. They contradict each other: one states that Ehrman left Christianity because the Bible was not inerrant, the other, because he could not reconcile God with evil.
This discrepancy can be explained away by pointing out that human beings are not single input robots. Human beings usually have multiple and competing (sometimes even contradictory) reasons for the things they do. A captain of industry might highly desire money and might also highly desire power. These may lead him to establish a corporation. Only rarely will one find a critic citing both reasons as the motivation for his actions. Usually, authors stick to a main motivation which complements the theme of the author’s point. In a text on Biblical errancy, Ehrman will highlight his struggle with the Bible. In a text on God, Ehrman will highlight his struggle with the problem of evil.
But Ehrman discounts this methodology for the Bible. To use Ehrman’s words against him:
This account, claiming both motivations to be true, is creating then a “mega-Ehrman” (for which we might as well throw in his other books which remain silent on the issue, for good measure)—a Ehrman found nowhere in his own writings but simply in our own heads, as we write a story of our own to substitute for the stories of the Ehrman texts. That is not the best way to treat the accounts of Ehrman’s conversion.
A common objection I have to Ehrman is “humans don’t work that way”. Ehrman prefers the mechanical approach to understanding complex human beings. One motive, one action. One author, one subject (as in individual). A more fluid understanding of any historical figure is to evaluate what each author says about the individual, and then form an image of a complex human being possessing complex inward struggles. Only when motives do not line up with the character should we discount them because they “conflict”.
the gospels are not novels on the life and times of Judas. In fact, Judas is a minor character throughout the gospels except in a few fleeting passages. None of the gospel writers ever claimed to have a complete character sketch of Judas, detailing all his innermost thoughts. They ascribed their own evaluations and talking points when discussing Judas. Just as Ehrman describes different conversions from Christianity to highlight different points, the gospel writers do the same.’
source: Christopher Fisher, “Ehrman on Judas’ motives” (realityisnotoptional).