Why do some people argue over god?

[kat_xk8]

Wars, politics and land seem to be a root of most wars, but what I don't get is why some religious people argue over god - such as "god can't " or "god won't " and "god never said" or god never promised such and such and could go on - can't god decide for himself or are some people appearing to not let him - I just don't get why people can't just say that's gods call or something like that - there is this statement let go let god - some people tend to let go but not god or let go let them - ugh