Richard Bauckham has written an excellent book called Jesus and the Eyewitnesses. I could write a long review but instead I'll just steal the words from another reviewer, Ben Witherington. He said this at the end of his review.
There is much more to interact with and commend in this fine book, but in a brief review we must be content with asking, What is the upshot of Bauckham’s discussion? It is that the original Christian Gospels need to be taken far more seriously as sources of reliable historical testimony about the life of Jesus, his words and deeds, his disciples and demise, and the aftermath thereto. They were neither created nor passed along in the form that modern form critics (such as Rudolf Bultmann and Martin Dibelius) thought. We do not have in those Gospels “cleverly devised myths” or stories only loosely based on history, but rather eyewitness testimonies and traditions that in many cases the witnesses were prepared to die for, so profoundly did they believe them to be true.
The Gospels were written by people who were indeed in touch with vivid eyewitness testimony about events that had been seared into their memory and had left indelible impressions. As it turns out, we may know more about the historical Jesus and his first followers than modern skeptics have suggested—far more, if Bauckham is right.