I think the issue here is conceiving of Gods Commands as the literal words - which is I agree fundamentalist, and Greek, tendency.
If I here from my neighbour that it is the Queen of Englands command that we in the Colonies should not eat ice cream on Sunday (or something equally absurd) I understand what ice cream is, that some authority has commanded it, and that there may be means and measures taken to enforce that command by my trust in my neighbour and how seriously he says that. All of this IS the Queen of Englands command not just because she 'says it' but because it fully manifests itself. The means and measures, all the ways it is communicated, and the way I come to understand it, which includes by my knowledge of our system of days and of 'what' l the essence of icecream are part of what could be conceived as her command - none of them are brought into being without the presencing of her command. All of this is what it is for her word to mean anything.
A more open but still historical and long present tradition interprets 'Gods Commands' in a similar way - Gods Word has a 'commanding form' in which it is apparent in a variety of ways that certain things are his will. The statement of what these ways are is a different question and possibly heavy contextual - hence even in Natural Law Theology, in which what is willed is understood through seeing things there is a primacy of conscience. If you hold there is "Good" that can be approached as "Good" non-reductively, which then you may hold that however you see it in any circumstance is the way it was communicated to you, as by your neighbour with the queens law, and that it is Gods Command in its Identity. For example no one would ask "Is it the Queens Law because it is the Justice of England or is it the Justice of England because it is the Queens Law?" as an intellegent response when the two things were defined as identical - it is precisely this command theory that is held in the Christian Tradition, Lollardy and its derivatives excluded, one simply believes that God is Moral and created the ways we are informed of his "commands" - his Commands can be Identical to what is Good without there being some contradiction - this is understood classically to be a confusion about actuality. If I create a game with rules did I make the rules so they encouraged one towards a playstyle though freedom was allowed for divergent, suboptimal paths and outcomes, or did the good outcomes be defined as good because I created the rules to lead to them? Both these things happen at the same time - there cannot be a game without outcomes and without spatio-temporal movement towards them in an old phenomenological sense. Being and Time are both part of the creation of the Game and the good can be described as an optimal pattern selected for Good throughout the game - if I tell you that I want you to go optimally through the game am I telling you to go through the game in an optimal way because it brings about the most good, or have I set it up so that there is an optimal way? Or when I set it up and had a notion of Good outcomes are not both things present and can it not be evident in the game that there are ways that are optimal by how I set it up? If at one point you come to understand that I want you, the player to be optimal as you understand the game more you see more of what is optimal - the Euthyphro question is perhaps the shallowest of all platos that anglosphere atheists work sites - its just semantics and misses the point.
The rhetorical questions are not to persuade but to illustrate rather than engage in deduction / induction discourse - this is as we are ultimately dealing with from my POV a semantic issue.
God, say the religious fundamentalists, is the source of all morality; there can be no morality without a Judge who rewards and punishes. If we did not fear hell and yearn for heaven, then what would stop people from murdering each other left and right?
Suppose Omega makes a credible threat that if you ever step inside a bathroom between 7AM and 10AM in the morning, he'll kill you. Would you be panicked by the prospect of Omega withdrawing his threat? Would you cower in existential terror and cry: "If Omega withdraws his threat, then what's to keep me from going to the bathroom?" No; you'd probably be quite relieved at your increased opportunity to, ahem, relieve yourself.
Which is to say: The very fact that a religious person would be afraid of God withdrawing Its threat to punish them for committing murder, shows that they have a revulsion of murder which is independent of whether God punishes murder or not. If they had no sense that murder was wrong independently of divine retribution, the prospect of God not punishing murder would be no more existentially horrifying than the prospect of God not punishing sneezing.
If Overcoming Bias has any religious readers left, I say to you: it may be that you will someday lose your faith: and on that day, you will not lose all sense of moral direction. For if you fear the prospect of God not punishing some deed, that is a moral compass. You can plug that compass directly into your decision system and steer by it. You can simply not do whatever you are afraid God may not punish you for doing. The fear of losing a moral compass is itself a moral compass. Indeed, I suspect you are steering by that compass, and that you always have been. As Piers Anthony once said, "Only those with souls worry over whether or not they have them." s/soul/morality/ and the point carries.
You don't hear religious fundamentalists using the argument: "If we did not fear hell and yearn for heaven, then what would stop people from eating pork?" Yet by their assumptions - that we have no moral compass but divine reward and retribution - this argument should sound just as forceful as the other.
Even the notion that God threatens you with eternal hellfire, rather than cookies, piggybacks on a pre-existing negative value for hellfire. Consider the following, and ask which of these two philosophers is really the altruist, and which is really selfish?
Blank out the recommendations of these two philosophers, and you can see that the first philosopher is using strictly prosocial criteria to justify his recommendations; to him, what validates an argument for selfishness is showing that selfishness benefits everyone. The second philosopher appeals to strictly individual and hedonic criteria; to him, what validates an argument for altruism is showing that altruism benefits him as an individual: higher social status or more intense feelings of pleasure.
So which of these two is the actual altruist? Whichever one actually holds open doors for little old ladies.