How does "God" give his commands? Is it through a holy book?
If so, doesn't that holy book need to be interpreted and explained? "Indeed, how could I understand without someone to guide me" -- a certain Ethiopian official was quoted as saying in Acts.
So to properly understand the commands, we would need guidance. But from who? That's where theocrats of various religions come in, and tell you how obedience to God should best be carried out for one's salvation.
Christian theocrats have directed people to fight in wars and to persecute minorities. Islamic theocrats have directed acts of terrorism against innocents. I could go on and on. But if the commands come through a book that must be interpreted, then we are relying on men (who are no more special than you or I) to tell us what obedience means.
On the other hand, if the comnands don't come through a book -- but by prayer, then everyone can invent their own way of interpreting what obedience means. And this happens frequently too.
For example, in the polgyamist LDS offshoot in Texas, the belief is that to obey God and get in the Kingdom, a man must have a minimum of 3 wives. So that's their way of obeying God, and they think they're just as right in belief as mainstream believers are.
All these crazy beliefs and people "obeying" God and doing terrible acts in the name of God is almost enough to make one an atheist.