Appeal to God doesn't really push in either direction on moral relativism, as Socrates showed with the Euthyphro question. If X is moral because God says so, then morality is just whatever God says it is, and thus morality is just as objective or relative as it would be in the case where morality is whatever I say it is. And if God says so because X is objectively moral, then I could just as well say so because X is objectively moral.