This is, and has been for centuries, considered by atheists and anti-moralists as the ultimate refutation of God. Specifically of Divine Command theory.
This dilemma basically goes as follows:
In Plato’s dialogue between Socrates and Euthyphro, Socrates is attempting to understand the essence of piety and holiness:
Socrates: And what do you say of piety, Euthyphro? Is not piety, according to your definition, loved by all the gods?
Socrates: Because it is pious or holy, or for some other reason?
Euthyphro: No, that is the reason.
Socrates: It is loved because it is holy, not holy because it is loved?
The dilemma Euthyphro faced is this: Is a thing good simply because the gods say it is? Or do the gods say a thing is good because of some other quality it has? If so, what is that quality? The problem stumped Euthyphro.
Russel put it this way:
If you are quite sure there is a difference between right and wrong, you are then in this situation: Is that difference due to God’s fiat or is it not? If it is due to God’s fiat, then for God Himself there is no difference between right and wrong, and it is no longer a significant statement to say that God is good. If you are going to say, as theologians do, that God is good, you must then say that right and wrong have some meaning which is independent of God’s fiat, because God’s fiats are good and not good independently of the mere fact that he made them. If you are going to say that, you will then have to say that it is not only through God that right and wrong came into being, but that they are in their essence logically anterior to God
First, I refer interested parties to the following sites: http://www.str.org/site/News2?page=NewsArticle&id=5236
and : http://www.charlesgfinney.com/1840skeletons/sk_lecture23.htm
These 2 sites offer or some good responses to this issue and teh Moral Law of in general. I will quote from one or the other in some small measure here.
Basically, no being can make law. But no law can exist without sanctions. And no sanctions can exist without a Ruling, conscious Magistrate to adiminster them…reason it farther - the ultimate conclusions are obvious enough - God’s existence is necessary to the existence of ultimates moral values.
However, nothing is easier than defining this *dilemma* out of existence. Why? Because there is no dilemma in the 1st place!
The pretended dilemma argues what it does not understand and founds it’s argument on a falsity, an incorrect presumption - that the moral Law and God are two separate things.
So, in one phrase it may be undone - “God is the Law and the Law is God.”
God is the inspirited, incarnate, Living Law - they are one. Not independant entities.
What is said of God is exactly what may be said of the Moral Law “the radiance of the glory of God and the exact imprint of his nature”. Every thing that one can discern of all true objective moral realities can also be said of God himself.
And of course, this is the view of the bible and Christianity. “Anyone who does not love does not know God, because *God is love*.”
Love is good willing. It is benevolence. It is seeking the highest good. “Love does no wrong to a neighbor; therefore love is the fulfilling of the law.” “For the whole law is fulfilled in one word: ‘You shall love your neighbor as yourself.’”
The Law is One. An indivisible unit all summed up in one word “love” - agape - disinterested, unselfish good willing. And that so describes who and what God is, that the two are inseparable, immutable, unchangeable and eternally, mutually existent - one in the other.
Thus no God = no law and no law = no God. And thus the existence of God = existence of Law vice versa. So the very existence of a real, objective Moral Law running everywhere where there are sentient, self-deteminingbeings, is evidence of the existence of God.
Just as both philosophers (check Kant on this) and theologians and simple everyday people have been saying from times immemorial.
“Do as you would be done by” is the worlds oldest, most universal command. It describes love which describes the Moral Law which describes who God is and what he is like.
As for the so-called tautologies and contradictions involved with the infamous “dilemma”, they are the very well documented territory of Darwinism and atheism as any one know if they’d really done any proper homework on the issue.