Ummm.... it is mentioned in ONE book so how can you say it was witnessed by many people. If I write here "the moon turned green with yellow stripes last night and it was witnessed by many people." that does not make it a fact. All writings about the origins of Christianity date from the second century or later. That makes them not much more than hearsay. Show me proof that is contemporary with the event, not a decade, not a hundred years later.
In my opinion there are two ways to look at that situation.
1) What was written was all bullshit and just an attempt to get a movement going. However, if that was the case then why was the Jesus bloke picked to be the centre of it all.
Or
2) Must have been some big stuff happened for someone to start writing about it a couple of hundred years later.
And if it was hearsay that does not mean the basic story is wrong.
Critics of the Bible often say that the people of those times would have been impressed if someone struck match. That is true. But that begs the question of why through all those Old Testament years has the basic story been the one that kept going.
I think the Bible at the very least is true to the extent that there was some heavy horsepower about the place, big enough horsepower for the story to keep going. Since people of those times were so easy to impress then one would expect the Bible to be just one of hundreds of such books.
Consider books today on something like diet/health. There are 100s of them. However if one had it right then 100s would not be heard of.
Like any history the inaccuracies would be high and the sory would be shaped. Until recent years The Little Big Horn was Custer' Last Stand and it has often been said his wife promoted that theme. Then when artifacts were uncovered it appears Custer and his men either froze on the spot or ran for their lives. However, the basis story is unchaned, that is, Custer and his men were masscred by a big collection of Indians.
I followed dinosaurs with geat interest all my life and that stuff is very fluid. We have gone from them being just like reptiles of today to being birds and now they are not birds but both from a common ancestor. But like Custer and The Little Big Horn, the basis are unchanged, that is. if you travel back a 100 million years the animals on average size would be much bigger thand today and very reptile like to look at.
Personally I find it impossible to believe a fairy tale can be supported by so many, all the Christians and Islamers and the Jews and for thousands of years. And the support is not limited to the totally uneducated, just the opposite.
Lastly, if the Bible was all fairy tales one would expect a counter Bible to have a come along for the ride.