The people who wrote the Bible were not liars or hallutinating people. To lie means to say something that it´s not true on purpose, with the intention of harming. As this people were not conciously saying such a thing, they´re not liars. They are telling events that may not account for the truth, but they´re not liars, because they think bona fide they´re telling the truth. They´re not hallutinating either, because it may mean that they´re taking drugs or that there´s something that alterates their conscience. What they were making is INTERPRETING reality with the tools they had at the moment, far more imprecise than ours, and they honestly thought that it was well-done.
Your second claim is illogical. Jesus never authored any of the Gospels and the people who wrote them probably didn´t meet him personally. That, together with the scarce references to Jesus in outside sources(there are though), are the root for the present scepticism. I mean, no book that intends to praise a person says that he´s a sucker or denies its existence but it is the book itself that should be validated, no the other way round. Second, scientists, even if they privately believe in God, as I do, my way of course, rely on EVIDENCE, in observable things. Ok, we asume that the universe started with the Big Bang, but behind the Big Band, is there anything?, some people say yes, some people say no, but to say that scientists think that one day God was bored created in six days a whole new universe is NOT BELIEVED by any scientist, at least in this planet. Second, they´re not trying to change any history AT ALL. In fact, they´ve never denied that America was discovered, or that there was a guy called Napoleon or yes, if there is evidence, that the Jews were deported to Babylon at around 500 BC. They do admit that, what they differ you with is in the interpretation you give. In fact, your last statement can be attributed to you, in order to substain your interpretation of God, you have to reach absurd levels.