However, Modeller, you're overlooking the Dead Sea Scrolls, referencing the Old Covenant. These ancient documents push back the window on the Old Testament by cneturies and... behold and low... they're nearly exactly identical to the one you can hold inyour hand today.
Look, can you name even one document from the first century that names an individual? Fact is you can't. Let alone one that provides the store of information about one individual (Yeshua) that's located in the Gospels and other New Testament copies we have today. The science that goes into verifying the information in any old document is extensive and well accepted throughout the world. The thousands of examples of copies of New Covenant documents is literally overwhelming when compared to the dearth of such documents on other subjects... plus, for all genaral purposes they are all the same... few and minor differences. Unfortunately, this is meaningless to chakka and perhaps yourself, but I find it impressive.
Lastly, the sources of the various copies come from all over the ancient world... meaning they would have been copied from earlier documents and had little chance at being part of a grand conspiracy to hoodwink everyone.
There are few if any respected historians that cling to the once popular belief that Yeshua never existed. That doesn't 'prove' his claim on history but it does establish a basis for at least giving the evidence close examination.
Men and women have died for belief systems, probably since the beginning of time... and, unfortunately, they've died for what was later revealed as a lie. Yet, there's no evidence I can locate of someone dying for a known lie. The persecution to the death of early believers was vicious and wide spread... yet all they had to do to escape was simply say "I no longer believe"... that didn't happen, or if it did it was very limited.
For my part, I can only attest to the difference in myself since I examined the evidence as a near-athiest... certainly an agnostic, and found the evidence deserved more than my total scepticism. Second Corinthians 5:17 says what I've found to be true. I've many friends that have come from different backgrounds... ranchers, manual laborers, Phd.'s, housewives, business owners, etc., etc., who all report basically the same thing...
Thanks for your input, though...
By the way, portions of verses believed (at least at this point) to have been from James (the brother of Jesus) have been found in the Dead Sea Scrolls, which could push the date of original writing back to within just a few years of the Christ's death, burial and resurrection. Several other portions are still being studied.
Lastly, 55AD is only 25 years after Jesus... if the writers, as you suggest, were adults of 20 to 30 yearso ld, they would have only been45 to 55 years of age... no?