I suppose you mean the question posed by Socrates: Is an action moral (pious) because it is loved (or commanded) by the gods; or is an action loved (commanded) by the gods because it it moral (pious)?

Let's take each possibility in turn, and see what the consequences would be of answer yes (or not) to it.

The first possibility is that an action is moral because it is commanded by the gods. That would mean that just because the gods commanded that you so do something, no matter what it was, it would be thereby, moral. So, if the gods commanded you to (say) torture a little baby to death, it would be a moral thing to do. The question you ought to ask yourself would be, why should the just the fact that the gods told you to do something, is what make the action moral, regardless of what kind of action it was? Suppose the gods told you to cut your toenails every third Friday, would that make cutting your toenails moral (or not doing so, immoral)? It doesn't make much sense, does it.

The second possibility, that the gods command you to do something because it is moral, means that the gods themselves are following a standard or morality independent of themselves. It is not because they command the action that the action is moral, but because the action is moral that they command it. There is an independent (absolute) standard of morality which even the gods must acknowledge.

The Euthyphro problem is a two-pronged dilemma. It is concerned with whether God makes moral truth or whether he instead recognizes moral truth. One of these prongs can lead to moral relativism while the other to moral absolutism (the metaethical view that certain actions are right or wrong irregardless of the context in which they are performed). I will show both prongs and their entailment since they are easily related.

The Divine Command Theory (DCT) rest on two premises and one conclusion:

1. If moral rightness only means that which is in accord with the will of God, and
   
2. If moral wrongness only means that which is not in accord with the will of God
   
3. Then, one need not consult moral reasoning independent of the will of God when attempting to determine moral right and wrong.
   

The DCT is a deontological position. It has three problems:

1. The question of God's existence; which questions whether moral laws are synonymous with the will of God.
   
2. How we are to interpret God's will; which religious view God is derived from?
   
3. Choosing which interpretations and translations to abide by.
   

The Euthyphro Problem (EP) poses two question to the DCT:

1. Is something moral because God wills it to be moral, or
   
2. Does God will something to be moral because it is moral?
   

If 1, then God could have willed something that is moral to be immoral and, therefore, God's will is arbitrary (and so is moral truth). Theists may try to appeal to the perfect goodness of God (his inability to sin); however, if God is incapable of sin, then God's omnipotence comes into question. A rebuttal is to say that God's omnipotence is his ability to do anything that is logically possible, however, this may still be considered a case of non-omnipotence. Furthermore, if theists believe that God's essential nature is perfect goodness, then opponents of the DCT may point out that God's will has been determined by his essence and, thus, God's freewill (omnipotence) is brought into question.

Next, if God is perfectly good, then it would also bring into question our ultimate praiseworthiness of God. The praise we usually bestow upon individuals is proportionate to the amount of obstacles they had to overcome in order to accomplish what we deem praiseworthy, yet if God is perfectly good, then he could not help but to do what he does.

Last is the redundancy problem. Since saying 'good' means 'that which God wills,' then when one says "God is good" one is saying "God is that which God wills." Thus, one is not attributing a moral property to God, but only to God's will. The claim that "God commands us to do what is moral" means the tautology "Gods commands us to do what God commands us to do." Meaning, we can gain no insight into the moral truth of things such as charity or the torture of creatures other than saying that God has willed or not willed it.

If 2, then either moral truth is independent of God (moral absolutism). This means that moral truth and God are autonomous, thus the position is known as the autonomy thesis. This does not imply that one originates from the other as they may have well been in eternal coexistence. Nevertheless, there are two version of the autonomy:the theistic and the atheistic version.

The theistic version generally follows that rational beings can arrive at moral truths by their own rational capacities independent of what the will of God says are moral truths. This is because God has given us the capacity to do so. Furthermore, they view our reason as finite (i.e. imperfect), therefore we need moral exemplars sent by God to keep us on the correct moral track or to better grasp the subtleties of what it means to be moral (e.g. Jesus, Buddha, Gandhi, etc.). Lastly, the theistic version believes that the notions of reward/punishment (blessing/curse) serve as motivation to live according to God's moral laws.

The atheistic version generally follows that it is ultimately our rational self-interest that allows us to arrive at the moral law. Our rational capacities allow us to see that being moral is in our overall self-interest inasmuch as it allows us to live happier and more fulfilling lives. It is partially due to evolution that our reasoning has become capable of allowing us to establish rational moral imperatives (e.g. social contracts). This means that morality is its own motivation, rather than the motivation of divine reward/punishment by the theistic version. Lastly, moral exemplars are usually explained as having a heightened moral sense or insight into human psychology and the human condition (i.e. a disposition towards increased moral inquiry and moral reasoning). This can most notably been seen in the works of Virtue ethicists.

I hope this has better explained any questions you may have had, and best of wishes towards your studies.

Thanks a lot Logan and Kennethamy! That was very helpful, merci beaucoup.