I enjoyed Scot McKnight's piece on the Historical Jesus, because much of it is important to say. Historical Jesus work is often deconstructive (the key word here is often). History at its best is reconstructive work, based in probability and working in a discipline that is severely limited in what it can deliver.
There are many historical Jesuses out there, and many have the face of the scholar who studies them in terms of his or her own desires for Jesus. Historical Jesus work cannot take the place of faith. The Jesus that the church and world deals with is the Jesus of the gospels. All fair points. But historical Jesus work matters, and it matters a lot. Here is why.
Contrary to what Scot suggested, no one claims that historical Jesus work gives us or seeks to give us an uninterpreted Jesus. Anyone who demands to be taken seriously as one sent from God (as Jesus did in his mission and work) comes with an interpretive package wrapped up in his actions. Historical work helps us get the context of those actions. How can one fully appreciate what the temple act (the "cleansing of the temple") meant without understanding Second Temple Jewish expectation that the new era would purge the temple and call people to a renewed righteousness? People who work only with the text of the Bible might miss this backdrop. It is precisely this kind of context that historical work gives us, or at least can alert us to, so we read our gospels more carefully.
As both Tom and Craig alluded to but I wish to highlight, there are different kinds of historical Jesus work. Some seek to reduce the data base of Jesus (and challenge the sources), but others seek to illuminate the sources and help to explain what is going on. Yes, we cannot "prove" it all, ...1