Let's put it this way. Do you accept the various theories that science presents under the pretense that if you had the proper equipment and knowledge you could replicate what you've been told? I highly highly doubt you've done an experiment for everything you believe is truth, if hardly any at all. Well I too have an authority that I have no reason to doubt, and Shakespeare's works I have read and seen with my own eyes. I've watched the LOTR movies and have seen occult truths in them, and so I have no reason to doubt that in an even more detailed book there are even more occult truths.
humans do not need god to be taught how to be good. i was a good person before i even heard of god, seeing as my parents raised me without any religion, thus giving me the choice later on. i wasn't indoctrinated at youth, like most religious folk are. i find that to be morally wrong.