Stephen Colbert is a parody of a right-wing talk show host. (Actually, he's more than just a parody; I think he's a complex mix of parody, sincerity, and humor for humor's sake.) Regardless of how serious the "actor" Stephen Colbert is, the "character" Stephen Colbert does a not-too-shabby job refuting Bart Ehrman, author of Jesus, Interrupted: Revealing the Hidden Contradictions in the Bible (And Why We Don't Know About Them).

The Colbert Report	Mon - Thurs 11:30pm / 10:30c
Bart Ehrman
colbertnation.com
Colbert Report Full Episodes Political Humor Gay Marriage Commercial

Hat tip to Catholic Answers Forums.

I have not read any of Ehrman's books and am unfamiliar with his arguments, but even in this short he shows apparent ignorance that makes me think his ideas are not much of a threat to the Christian faith. When, in Mark's Gospel, Jesus cries out, "My God, my God, why have you forsaken me?" he is not expressing simple despair, as Ehrman believes. He is quoting Psalm 22. The Jews, including Jesus and all the other Jewish witnesses, would know the whole psalm, which is a prophecy of the crucifixion. Consider verses 20-25:

But you, LORD, do not stay far off;
my strength, come quickly to help me.
Deliver me from the sword,
my forlorn life from the teeth of the dog.
Save me from the lion's mouth,
my poor life from the horns of wild bulls.
Then I will proclaim your name to the assembly;
in the community I will praise you:
"You who fear the LORD, give praise! All descendants of Jacob, give honor;
show reverence, all descendants of Israel!
For God has not spurned or disdained the misery of this poor wretch,
Did not turn away from me,
but heard me when I cried out.

Considering the entirety of this prophetic song, Mark's version of Jesus does not seem so different from Luke's stalwart version of Jesus, after all.