In an earlier article, I wrote about a question for divine command metaethics, a question that I called the Moral Grounding Question.
Moral Grounding Question (MGQ): In virtue of what do God’s commands ground moral obligations? (or, in virtue of what does God have MG-power?)
In that previous post, I explained the moral grounding question and showed that it is a question that defenders of the Divine Command Theory (DCT) need to answer. I also argued that one possible answer to MGQ, namely that God has MG-power in virtue of being omnipotent, is not very promising. In this post, I will examine another potential answer to MGQ: the suggestion that God has MG-power in virtue of his authority.
While I think that you can find this view in various incarnations throughout the DCT literature, I will focus on the recent work of C. Stephen Evans, specifically his book God and Moral Obligation. While Evans does not raise the MGQ in the manner that I have, I think that it is not difficult to, on the basis of what he does say, construct the kind of answer Evans would offer.
In God and Moral Obligation, Evans defends a version of DCT that he claims is most similar to that of Robert Adams: “the kind of view that I find most attractive is the type defended by Robert Adams. Adams sees moral obligations as identical to the commands of a good and loving God, or the commands of God understood as essentially good and loving.”  I have written previously about Adams’ view on this blog and I will have more to say about it in a little bit.
Evans works hard to motivate this view and in the process provides an account that offers a coherent answer to MGQ. I’ll quote from a couple of relevant passages from Evans and then I’ll articulate what I take to be Evans’ answer to MGQ.
A proper social relation with God is one that requires humans to recognize the enormous debt of gratitude they owe to God, as well as the value of an on-going relation to God. Most religious believers have seen this relation to God as one in which God rightly has authority over them. This authority might be explained in various ways, as stemming from God’s ownership rights as creator, or as grounded in the gratitude owed to God for God’s good gifts, or as grounded in the goods which a relation to God makes possible. 
A divine command theory of moral obligations sees the relationship of creature to creator as a distinctive kind of social relationship which carries with it certain obligations, just as is the case for such purely human social relationships as parent to child. In particular, a DCT requires that God possess legitimate authority, so that his commands (or expressed requirements) establish obligations for his human creatures. But it is clear that some normative principle or principles must be the basis of this authority. 
From these two passages, it is pretty clear that Evans’ answer to MGQ would be in terms of God’s authority. The view is that God’s commands constitute moral obligations in virtue of the fact that God, given his status as creator and provider of goods, has the right kind of authority over his creatures. Evans recognizes that this account is subject to what he calls the “prior obligations objection.” This objection says that God’s commands can only constitute moral obligations if there is a prior obligation to obey God’s commands. Evans spends a bit of time trying (unsuccessfully, I think) to respond to this objection (pp. 98-101); in a subsequent post I will take a close look at his response. However, for the remainder of this post, I will be showing why, prima facie, an Evans-style answer to MGQ will not suffice.
To be clear, the view I am considering, which I will call the Authority Answer to MGQ (AA), is as follows:
Authority Answer to MGQ (AA): God’s commands constitute moral obligations in virtue of the fact that God has authority over his creation.
AA is not a satisfactory answer to MGQ. The reason is that AA implies that there exist deontic moral facts that are prior to God’s commands; and the existence of deontic moral facts that are prior to God’s commands is inconsistent with a divine command metaethical account of moral obligation. Let me explain these points:
AA implies something I’ll call the Authority Thesis:
Authority Thesis (AT): God has authority over his creation; in particular God has authority over created beings.
AT is a deontic principle, or at least it implies deontic claims. In particular, it implies that created beings are obligated to obey God. That it implies this is, I think, pretty obvious. After all, if created beings are not obligated to obey God, what sense can we make of the claim that God has authority over created beings? To say that God has authority over human beings is just to say that humans owe obedience to God or that humans are obligated to obey God. I cannot make any sense of the claim that God has authority over created beings that does not involve the claim that created beings are obligated to obey God (so, if you have some alternative account of the authority thesis, please let me know).
Now, AA is not consistent with a divine command metaethical account of moral obligation. This is a very important point and to help make it, I am going to rely on the work of Mark Murphy, a philosopher at Georgetown University and one of the leading experts on divine command metaethics. In his book, An Essay on Divine Authority, Murphy defines divine command metaethics as follows:
For a view to be a version of divine command metaethics—hereafter ‘DCM’—is just for it to be an attempt to explicate normative properties or states of affairs in terms of God’s commands. 
On a metaethical divine command theory such as Adams’, there is no further deontic principle upon which God’s moral grounding power depends. However, AA claims that God’s moral grounding power depends upon a further moral principle, namely AT. So, a view according to which our obligation to obey God is based on God’s authority (in other words, AA) is not a version of a divine command theory of moral obligation. Rather it is a Normative Divine Command Theory (NDCT). Here is Murphy on normative versions of divine command theory:
Normative versions of divine command theory assert that the supreme moral principle is that God’s commands are to be obeyed. The principle that God is to be obeyed is, on normative versions of divine command theory, supreme due to its status as an independent moral principle that is the source of the correctness of all other moral principles. It is independent, lacking a source in any other moral principle: the principle that God is to be obeyed is fundamental. It is the source of all other moral principles: any moral principle that binds created rational beings is to be explained in terms of the principle of obedience to God. 
Importantly, on NDCT, moral obligations are not grounded in divine commands but rather in the obligation to obey God. The ultimate bedrock of moral obligations is not God’s commands, but the principle that God’s commands are to be obeyed. And, of course, the obligation to obey God is not grounded in a divine command; it is true independent of any divine command. Suppose, then, that God commands that we tell the truth. In this case, on NDCT, we are morally obligated to tell the truth. But it would be wrong to say that this moral obligation is fully accounted for in virtue of the fact that God commands it. This is because the principle that we are obligated to obey God is also necessary to ground the moral obligation. Indeed, on NDCT, every moral obligation is ultimately grounded on the general obligation to obey God. So, on NDCT, God does not have moral grounding power in the requisite sense; moral obligations are not fully constituted by God’s commands. Rather his commands create moral obligation only via the moral principle that God is to be obeyed.
Here is the upshot: AA is an attempt to account for God’s moral grounding power. But if AA is true, then AT is independent of God’s commands. But if AT is independent of God’s commands, then Adam’s divine command theory is false. And if AT is independent of God’s commands, then God’s commands do not ground moral obligations; rather moral obligations are grounded in AT.
Think of it this way: On Evans’ view, in virtue of what is AT true? Either it is true in virtue of God’s commands or it is not. If it is true in virtue of God’s commands, that just means that we are obligated to obey God because God commands that we obey God. So, AT is true because God’s commands have moral-grounding power. But if so, then AT cannot account for the fact that God’s commands ground moral obligations. That is, AT does not answer MGQ since AT depends for its truth on the fact that God’s commands ground moral obligations and so cannot explain that fact. If AT is not true in virtue of God’s commands, then there is at least one moral obligation (the obligation to obey God) that is not identical with a divine command. Thus, divine command metaethics is false. In particular Adam’s version of DCT (according to which all moral obligations just are divine commands) is false.
So, AA cannot be the correct answer to MGQ. God’s authority cannot explain why God’s commands have moral grounding power. 
 Evans, C.S. (2013) God and Moral Obligation. Oxford: Oxford University Press. p. 26
 Ibid., p. 28
 Ibid., p. 64
 Murphy, M. (2002) An Essay on Divine Authority. Ithaca: Cornell University Press. p. 71
 Ibid., p. 6
 As I indicated above, Evans is aware of the problem I have identified and does try to address it. I don’t think his response is at all compelling. I will explain his response and argue that it fails in a follow-up post.