What is "Good"?
Many Christians posit that there is an absolute standard of action and behaviour that we can call "good". The congendum of this position is that certain actions and behaviours that are always wrong no matter the time, place and circumstances that surround them.
Many Christians further propose that this absolute standard of behaviour and action is documented in the Bible. It is not unreasonable to backtrack from this theory and state that said Christians believe that "God is Good".
Does this mean that Christianity believe that everything that God does or tells us to do is "Good"? What if God tells us to obliterate an entire nation, or torture a room full of children to death (and there is precedent for such commands)? Would those actions be good? What if God tells us to execute all homosexuals merely for being homosexual? Some Christians apparently believe that this is what God wants, and consequently, that such action would be good.
This dilemma is far older than Christianity, and was first explored by Plato in the dialogue Euthyphro. Are good things good because God loves them, or does God love them because they're good? The dilemma asks the question of whether value can be conceived as the consequence of the choice of any mind, even a divine one? In short, are actions and beings "good" simply because God says so, or because God recognises their essential goodness?
On the first option the choice of God creates goodness and value. Even if this is intelligible it seems to make it imposible to praise God, for it is then an empty truth that God chooses the good.
On the second option we have to understand a source of value lying behind or beyond even the will of God, and by which His choice can be evaluated. If this is indeed the case, then God is not "God," but merely another entity; a greater entity than ourselves, with greater powers and so on, but an entity none-the-less
The dilemma arises whatever the source of authority is supposed to be. Do we care about the good because it is good, or do we just call good those things that we care about? It also generalises to affect our understanding of the authority of other things: mathematics, or necessary truth, for example. Are truths necessary because we deem them so, or do we deem them so because they are necessary? What is a "necessary truth" and can it have any meaning?
Aquinas responded elegantly to the dilemma by saying that the standard of good is formed by God's nature, and is therefore distinct from his will, but not distinct from him.
But there is a problem here. Is the universe a creation of God's will, or of God's nature, and if of the will, is creation in some sense a reflection of the nature of God? If one takes the view that it is, then whenever God performs a miracle, He goes against his own nature by breaking the laws of the universe, which are in some sense an analogue of his nature. The import of this is that God is capable of acting against His own nature, and thus of acting in a manner that is not good. God, it seems, can act in an evil manner. See Miracles..