Thesis: If God exists, then anything is permitted.
(To be more precise: If God exists, then anything that actually happens is permitted.)
Assume that God exists. Then God is the creator of the actual world, God is omnibenevolent, and God is omnipotent. So God created the actual world, and, because of His omnibenevolence, He did so as well as He could. But because of His omnipotence, a world that is as good as He could make it is one that is as good as one could be. Thus the actual world is among the best of all possible worlds.
Other things being equal, pain is bad. Pain can be good because it is deserved, and pain can be necessary because of its consequences.
A best of all possible worlds would contain nothing unnecessarily bad. Undeserved pain that is not necessitated by its consequences is bad, and it is not necessary; thus, it is unnecessarily bad.
But the actual world is among the best of all possible worlds, so it contains nothing unnecessarily bad. Thus is contains no undeserved pain or pain that is not necessitated by its consequences. Thus all actual pain is deserved or necessary because of its consequences.
That includes any pain that I might deliberately cause. Thus, if I deliberately cause pain, that pain will be deserved or necessary. E.g., if I deliberately torture babies to death, in front of their helpless parents, the pain, both of infant and parent, will be deserved or necessary.
It is permissible to cause deserved or necessary pain. Thus, it is permitted to torture babies to death in front of their helpless parents.
If it is permissible to torture babies to death in front of their helpless parents, then anything is permitted.
Thus, if God exists, then anything is permitted. QED.
If there is a religion that could form the basis of some kind of morality, it is not a religion with a monotheistic deity or one that creates the universe and is omnipotent and omnibenevolent.
From Rand to Reason 
If I remember correctly Simone Weil dealt with this by arguing that a thing only became necessary after it had happened. Before it happened it was not, from a human PoV inevitable therefore if morality would lead you to oppose it then oppose it you should. Likewise if morality would prevent you from carrying out a particular act then you should not carry it out. God may be able to bring good out of evil but that doesn’t make evil good.
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The point is that whatever actually happens will have been for the best. It’s true that what I’m going to do isn’t necessary (so far as I can tell) until I’ve done it, but, having done it, I’ve gone to show that it was part of the best possible world. At that point, I’ve shown that it would have been immoral of me not to have done it.
If I know that, having done something, I will rationally approve of having done it, shouldn’t I do it? (Unless what “it” is is distorting my access to information so that my future rational approval will be ill-informed or something.”
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An action has several component parts notably the physical act itself and the intention which precedes and accompanies it. None of the consequences of the act, whatever they may be, can alter the intention which you had at the time of the act. If you committed a morally evil act intending it to be morally evil then you are morally culpable for that intention. That God will bring about good consequences despite your intentions and indeed contrary to them doesn’t transform those intentions from evil into good. If you intend a good consequence then you require to use good means. If you intend an evil consequence then you cannot want or expect God to thwart your intentions.
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But the intention is to make the world more perfect by torturing a baby to death in front of his horrified parents, in the full knowledge that, since that event will occur, it will have been for the best. It’s just God working His wonders in mysterious ways, just as He does with less intentional human assistance all the time. The problem is that no consequence can be evil, so anyone who knows that can’t intend an evil consequence, or have evil intentions.
The inspiration of this point is this. Imagine that a religious person suffers the most indescribable horror: the kidnapping and murder of his or her child. What will his or her religious friends say in consolation? “It was God’s plan.”
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Not sure why you’d assume God would be omnibenevolent or ominpresent, even if God is a creator.
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Because that’s the definition of ‘God’, as traditionally construed; if God doesn’t have those qualities, the traditional arguments for His existence are even worse failures than they actually are. A God without will or intellect — Spinoza’s God, which I think is one of several incompatible ideas in the traditional idea of a personal God — would not present this problem.
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Which tradition? Not any tradition that I’ve ever subscribed to. Sounds like a kindergarten version of Christian thoughts about what a god would be.
Why wouldn’t a God-as-Creator be interested in seeing what we did with free will?
Why would a God-as-Creator necessarily be omnicompetent?
Of course, I’m not a Professional Philosopher, so I may have wandered into territory where words are actually terminology. If so, my apologies….
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It’s the Scholastic God. Given that God created a deterministic universe, and is omniscient anyway, He can’t be very interested in the unpredictable-by-Him. What would it be for something to be doable, but not doable by God?
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Is God gives commandments because they are good or they are good because God gave them? In the first case God is not a source of morality. In the second there is no choice between good and evil and therefore no morality at all.
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There’s more about the Salmieri book (and an excerpt):
http://www.wiley.com/WileyCDA/WileyTitle/productCd-1405186844.html
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