Wes Morriston, philosopher from University of Colorado, Boulder, writes an excellent  paper against divine command theory and specifically attacking William Lane Craig. The guys over at secular outpost (or as I like to call it, "Kill Bill's ideas) link to that article. Divine command theory in it's simple direct form says that what is good is that which God commands and it is good because God commands it. The paper is very long and covers a lot of ground, I have isolated what I think is one of the key points and i will deal with just that small but important section: the ground of moral duty as grounded in the divine.
Craig is answwering the Euthyphro dilemma, This is a problem raised by Plato in the from of Socrates question to Euthyphro, " is found in Plato's dialogue Euthyphro, in which Socrates asks Euthyphro, "Is the pious (τὸ ὅσιον) loved by the gods because it is pious, or is it pious because it is loved by the gods?"  The answer Craig takes to it is one I have also argued for years, that the good flows out of God's character so it's neither arbitrary now does it constitute a standard above God.
Morriston takes issue with Craig at the point where he says the good "flows out of God's character.
One might wonder about the phrase ‘flow necessarily from his moral nature’. Does it mean that each divine command is necessitated by God’s moral nature – that God’s moral nature makes it impossible for him not to command what he does in fact command? Or does it mean merely that it is necessary that all divine commands flow from God’s moral nature, where the ‘flow from’ relation is understood in a weaker sense ?Craig doesn’t say.
He's really conflating two different issues here: (1) do all commands flow equally from God's nature (2) could god chose to violate his nature? The question here is still veg because we are talking about Biblical commands? Or, are we talking about the human capacity to be moral itself? The latter is the kjey to the answer. Paul tells us the moral law is written on the heart (Romans 2:6-14). C.S. Lewis shows a great harmony in many Axial age civilizations as far flung as Briton and China. Although there are problems will will bracket them for fn. These similarities of course don't prove divine inspiration but they may indicate that if human moral nature is God given then God's commands must be generally flowing through that basic moral nature and even though filtered through cultural constructs the basic sense of moral goodness grounded in agapic sense of human dignity is possible universally. So the latter "weaker sense" would come closer to the answer, although I would not think of it as "weaker."
But whatever the details, it’s clear that the main point of the claim that God’s commands ‘flow necessarily from his moral nature’ is to head off a familiar objection to the divine command theory. It will be convenient to refer to it as ‘ the arbitrariness objection’. It goes something like this. Either God has good reasons for his commands or he does not. If he does, then those reasons (and not God’s commands) are the ultimate ground of moral obligation. If he does not have good reasons, then his commands are completely arbitrary and may be disregarded. Either way, the divine command theory is false.That's a fair assessment of the dilemma, and the answer is all moral motions ultimately point to love. God's character is love, thus there is warrant for the assertion that Divine love stands behind morality that God's commands are neither arbitrary nor are they stemming from a source higher than God. "Those reasons" are bound up in God's character, They are of concern to God because he is love. Obviously they are not "completely arbitrary since they arise out of the same basic aspect of who and what God is. The question about the goodness of reasons is transgression upon the concept of the transcendental signified. Truth is what is and the basis of what is is the ground being ie God). Thus God's reasons are a priori good not because they arbitrarily manufacture good via command but because they stem from the nature of God which is the ground of being. This idea that God's commands are arbitrary ( the "arbitrariness objection") is regarded as an ace in the hole by many skeptical philosopjhers.
Some philosophers think the arbitrariness objection is decisive (Shafer-Landau (2004), 80–81). But Craig thinks his version of the divine command theory is completely untouched by it. To see why, consider the duty to be generous to those in need. On Craig’s account, we can endorse all three of the following claims.
(A) God has a good reason for commanding generosity: generosity is good.
(B) Generosity is good because, and only because, God is (essentially) generous.
(C) Nevertheless, it takes a divine command to turn generosity into a duty for us.
Given (A), it might be thought that there is nothing objectionably arbitrary about God’s commanding generosity. Given (B), the goodness of God’s reason for issuing this command is rooted in his moral nature; it is not therefore independent of God. (C), finally, assures us that it is God’s command, and not merely the goodness of generosity, that raises it to the level of a moral imperative.I take issue with the last sentence and with B to which it refers. "Generosity is good because, and only because, God is (essentially) generous." Basically true but it requires some tweaking that zi think matters. It's not just that God is generous so requires that we be generous but that generosity is a of love, it's an expression of love in the agapic sense., The reason It is played that generosity is good only because God is generous is to avoid the prospect of atheists claiming they can be generous without God. Of course that's begging the question unless it's answering a certain kind of moral argument for God. If God exists it's legitimate to think that goodness flows from God's nature, If there is no God we are just Whistling in the dark anyway. From a purely metaethical standpoint generosity could be grounded in any number of things such as social contract theory, but they would all have a hard time establishing an ought denontologically without going teleological. It would be more certain to assume grounding in God. But switching from answering Euthephro a God argument would change the trajectory of the answers.
"Many questions remain. Could God have failed to command generosity? Could generosity have failed to be a duty ? Just what degree of generosity is required ? And why did God choose to require just that degree of generosity rather than some other ? " If love is the background of the moral universe, as is my assumption, (ala Joseph Fletcher)  then the direct proximity of God's will to a specific command might be less important in terms of metaethical theory than understanding the nature of love. In other words, rather than seeking to pin down a list of rules we need to be seeking ways to learn to love people. Of course that doesn't mean it's unimportant that God issues a particular command. Yet the important thing is not keeping rules but internalizing values of the good.
At this point he moves on to a second objection. If God turned around tomorrow and ordered something that is now evil such as eating children would it then become good to do so? Craig says can't happen it's opposed to God's nature. That should be enough for rational people. But if you are an atheist looking to throw a wrench in the works of belief, or a philosopher, no it's not. If you are both well better start looking for that eye of the needle. "Even if such commands are incompatible with God’s nature, isn’t it still true that according to the divine command theory eating our children would be morally obligatory if – per impossible – God commanded it?" It's another version of can God make a rock so big he can't lift it? The answer I've always given to that is "why should we expect God to do non sense.?" It's a cleaver question for skeptics to ask because it's a perfect double bind. If we do say "well theoretically if God did command even God would be wrong," we have relativized God's authority. If we say no we relativize his goodness. Either way we make belief in higher power seem silly.
Morriston kind of concedes that the question doesn't make sense and thus it doesn't matter what is said but he still concludes in such a way as to raise doubt with the oblivious:
Remember that for Craig God is, necessarily, a perfect being. If that is understood, then it really doesn’t matter to Craig’s position whether it’s impossible for a perfect being to command such a thing. Why ? Because if a perfect being commanded it, the being would have a morally sufficient reason for doing so; and if – per impossibile, perhaps – a perfect being had a morally sufficient reason for commanding us to eat our children, we should do it. If I am right about this, then Craig’s divine command theory escapes refutation – not for the reason he gives, but rather because the alarming-sounding counterpossibles implied by it turn out to true! 10 What’s so special about being God-like? Given fairly standard assumptions about God’s moral nature, 
The real problem is that the skeptics have underrated the scope of God's relation to reality. We are not just talking about the most powerful being. They approach it like the question is "this powerful guy is not like this but what if he was.?" It's not about the will of a powerful guy. It's about the nature of reality and trust and the relationship of that to love itself. Like the rock issue I refuse to believe that truth can be stumped by nonsense. Truth is what is (a simplified version of correspondence theory) and God is Being itself. Love is the background of the moral universe because God is love and God is the basis of reality. Thus if God is love, truth, and being. Thus morality is an extension of the good, and the good is wrapped up with the nature of truth and being. We must understand particular moral codes as best we can having filtered moral motions through culture. There is a reality back there behind it all that can't be cheated by questions like the one about the rock.
 Wes Morriston, "God and the ontological foundation of morality," Religious Studies, Cambridge University Press 2011 (2012) 48, 15–34 f doi:10.1017/S0034412510000740 URL:
http://spot.colorado.edu/~morristo/DoesGodGround.pdf accessed 2/27/2016.
WES MORRISTON Department of Philosophy, University of Colorado, Boulder, CO 80309-0232 email: Wes.Morriston@Colorado.EDU
 Morriston, op. cit. 18.
 C.S. Lewis, The Abolition of man: With Reflection on Education With Special Reference to The Teaching of English in the Upper Forms of Schools. New York, NY: Harper One, 1971, 83.
The problem with this is that it's limited to a segment of history from a period known as the Axial age, roughly from the 900 to 200 BC. The term is from Karl Jaspers. It excludes new world, Africa, Russian steppes and times before and after. Bit it is probably the best attempt to show universal moral sense. It does at least show large segments of humanity share similar moral motions.
 Morriston, op.cit., 18-19
 Ibid. 19-20
 Joseph Fletcher, Situation Ethics The new Moraloty.Louisville, Lomdon: Westminster John Knox Press. 1966, 58.
Fletcher discusses the same dilemma but not by the name "Euthephro." He discusses the nominalist position and argues that modern ethical thinking is nominalist and that is what's wrong with it. That's why philosophers ask questions about this dilemma because they can't ground moraloity in love since they are reductionists and can't understand values.
 Morriston, op cit.,20-21