This is often referred to as the Euthyphro Dilemma. I will let WLC take it from here…
Within Christianity, I think we are obligated to agree with WLC as he explains the case above. But in an argument about theism itself, it probably doesn’t matter. Say God did command morality (as Kiekegaard seems to believe with his teleological suspension of the ethical). What are the atheists going to do about it? The creator of the universe, a theoretical all-powerful being who has created everything and morality itself (if we take the argument as true) has commanded you to do something (luckily, that something seems to be encourage growth and love in humans). What are you going to do? Cry about it? Wail at the unfairness? Not believe in God? Or try to live in harmony with that law so that if there is any sort of eternal existence of which you might partake, you may?
An ant has no quarrel with a boot. You and I are just lucky that the boot loves us and commands us to love other ants…