A single question organizes most of the philosophical argument between ethics and theology: is an act good because a god commands it, or does a god command it because it is already good. Plato posed the question in the Euthyphro, asking whether the pious is loved by the gods because it is pious, or is pious because it is loved by the gods. Both branches carry a cost. If goodness is whatever a god commands, morality appears arbitrary, since the same god could in principle have commanded cruelty and made it good. If goodness stands independent of divine will, a god's commands become reports about a moral order that god did not create, which sits uneasily with the idea of a sovereign creator.
Historic responses split along the same fault line. Thomas Aquinas answered through natural law, holding that god's commands express a rational order built into creation itself, so the command and the good are never actually in tension. Duns Scotus and William of Ockham leaned further toward divine command, holding that the moral law binds because god wills it and could, in principle, have willed otherwise. Contemporary versions soften the dilemma rather than resolve it outright. Robert Adams argued that god's commands are constrained by god's own necessarily loving nature, so morality is neither arbitrary nor external to god. The debate remains active because both horns protect something a tradition does not want to give up, either divine sovereignty or moral objectivity.
Sources The Oxford Dictionary of the Christian Church, 3rd revised editionF. L. Cross and E. A. Livingstone (eds.) with Aquinas' Moral, Political, and Legal Philosophy (Stanford Encyclopedia of Philosophy entry)John Finnis