One thing I find frustrating, Micro, is that the earliest Bibles weren't written and compiled until almost 300 A.D. http://en.wikipedia.org/wiki/Dating_the_Bible. The only partial exception is The Deep Sea Scrolls, which I don't believe is represented in any of the current Christian bibles?
http://en.wikipedia.org/wiki/Dating_the_Bible
When you look at these early compilations, they differ substantially, in many regards. What concerns me the most is that they are clearly POLITICIZED. First of all, things don't get written down by the people who actually were there, but are written HUNDREDS of years later. Also, it must be that they are POLITICIZED, as the early compilations clearly require organized efforts by people with money and power sufficient to pull together groups of monks to hand script beautiful compilations. FWIW, all I mean by the word "politicized" is that Rulers are involved in funding and, presumably, approving the organizing, translations, and what is put in vs. books which are kept out.
(Buddhism faces a similar problem but, in the case of Buddhism it is WELL established that, from the beginning, Buddha's discourses were formally presented, by Buddha, in front of groups of monks and that they monks were charged to retain what Buddha said, with pretty high fidelity, by groups of monks memorizing his discourses word-for-word and reciting them amongst themselves to train younger monks to memorize them, word for word, accurately.)
So I am not trying to discount the Bible, but -- again -- the earliest extant written books date to about 300 years A.D., and many of them came hundreds of years later, or involved translations of translations, or were officially sanctioned by KNOWN Rulers (who presumably wanted to keep on Ruling).
I'm not saying that the books aren't spiritual nor that they don't contain, to a considerable extent, a common thread. But ultimately it comes down to human failings, historical vicissitudes, and HIERARCHICAL Ruling bureaucracies. To put this last point into context we can all appreciate: look how poorly even the written U.S Constitution has weathered 250 years, due to people who find the words inconvenient.