You clearly are mixing religious belief with reality. Fact is the Bible was written not by Jesus, and whether any of it is true or not is unknown. What we do know is that in 325AD a council near enough created modern day Christianity:
You can still be a Christian and accept how it was made btw.
The old Testament was written before either Plato or Constantine, and Jesus was referenced in EVERY book of the bible(bet you didn't know that:P)