I think Dawkins had it right when he stated that it mostly depends where and when you are born to determine what your belief system is. EG. If you were born in ancient Greece you'd probably worship Zeus. If you were a Viking you'd worship[ Odin. ..and so on and so fifth.
Therefore, I challenge anyone to justify why they just happen to believe in the god more appropriate to their own era and culture.
....and just why are there so many sects within a religion. Doesn't that alone prove that such a god is a useless communicator?