Are the gospels reliable sources on the life of Jesus? There is a wide gap between the scholarly rigor that historians use to research the past (to conclude that an interpretation of history is "most likely") and the arguments made by Christian apologists (to conclude that the biblical narrative of history is "truth"). Below is a concise explanation of scholarly standards for deciphering history, and why the gospels do not meet that criteria.
Note that this doesn't make them false, it simply means that they are unreliable historical accounts. They can be believed on faith, but there is little historic justifications for believing they're true.
Bart D. Ehrman is an American New Testament scholar, currently the James A. Gray Distinguished Professor of Religious Studies at the University of North Carolina at Chapel Hill.
The presentation was part of a debate hosted by the Southern Evangelical Seminary. Links to the entire debate below. I haven't had a chance yet to watch them myself, but if I have anything to add when I do I'll post a follow up. Part 1 Part 2 Part 3 Part 4
Unfortunately the video is edited by someone trying to argue "The New Testament isn't true, therefore the Koran is." Obviously a false dichotomy, equivalent to creationists saying "X is a challenge to how evolution is taught, therefore creation/intelligent design must be true."
Don't let that take away from what Dr. Ehrman is saying though, the video is still an excellent summary of what textual critics, even in many evangelical seminaries, have to say about the reliability of the Christian texts.
In search of reason,