Many people believe in Jesus but that doesn't necessarily make the stories about him true. What do historians, both believers and unbelievers, conclude about Jesus? How much about him can we know, and how much is a matter of faith?
Historical scholars don't believe that everything recorded in historical documents is true. Instead they test everything (see Are the gospels historical? for more about this), concluding that some things are well established, somethings seem unlikely to be true and some things cannot be determined one way or the other.
Most historians who have studied the New Testament period agree that, even by the demanding standards of historical study, we can be confident of many details of Jesus' life. For example, E P Sanders concluded:
Historical reconstruction is never absolutely certain, and in the case of Jesus it is sometimes highly uncertain. Despite this, we have a good idea of the main lines of his ministry and his message. We know who he was, what he did, what he taught, and why he died. ..... the dominant view [among scholars] today seems to be that we can know pretty well what Jesus was out to accomplish, that we can know a lot about what he said, and that those two things make sense within the world of first-century Judaism."
Most historians would agree with this, a few would be more sceptical and a larger number would be more positive about how much we can know. In the information below, I have stayed with careful and respected scholars who represent the broad consensus of New Testament scholarship, and not followed either the highly sceptical or strongly christian scholars. (For more on the range of scholarly opinion, see Which historians should we trust?.)
The following summary of what we can be confident of historically is drawn from E P Sanders, N T Wright and Michael Grant (note that Grant's list contains some items not in Sanders' list):
Of course a small number of scholars are more sceptical. For example, the Jesus Seminar concluded that only about 15-20% of what is recorded in the gospels can be viewed as probably historical, with the remainder split between text that those scholars considered unhistoric, and text which they could not judge whether it is historic or not. The Seminar included in the "historical" category such matters as:
This 'minimum' is still a significant list which more or less coincides with what can be gleaned from the non-christian Roman and Jewish sources (summarised by historian John Dickson).
On the other hand, there are many more scholars who argue that the historical evidence allows them to believe that the New Testament is almost entirely accurate history, with only a few small historical matters in significant doubt. Historian E Judge:
An ancient historian has no problem seeing the phenomonon of Jesus as an historical one. His many surprising aspects only help anchor him in history. Myth and legend would have created a more predictable figure. The writings that sprang up about Jesus also reveal to us a movement of thought and an experience of life so unusual that something much more substantial than the imagination is needed to explain it.
With this historical background, it is difficult to write Jesus off. We may choose to believe in him and the trust the authors who wrote about him, or we may simply accept him as a historical person who we don't find relevant. But the evidence makes it difficult to honestly write him off.
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