The stronger version holds that moral behavior is good in itself, as such, we should live in a particular manner since God wills it. Similar to the weakest version, this entails the only religious believers need to concern themselves with moral accountability. The strongest version asserts that moral behavior is good because it is willed by God. ("Faithnet")
The divine command theory is said to have been disproved by the Euthyphro dilemma, dubbed after Plato's dialogue, which goes: "Are morally good acts willed by God because they are morally good, or are they morally good because they are willed by God" ("Philosophy of Religion")
If one accepts the first argument that morally good acts are willed by God because they are morally good, the independence problem arises. This means that the argument itself is inconsistent with the theory since moral value becomes independent from God's will. ("Philosophy of Religion")
On the other hand, should one hold the second argument that morally good acts become such because they are willed by God, then problems pertaining to arbitrariness, emptiness and repugnant commands are contended with. The arbitrariness problem stems from the argument that the divine command theory seems to attribute morality only on God's whims.