The concept of omnibenevolence stems from two basic ideas of God: that God is perfect and that God is morally good. Therefore, God must possess perfect goodness. Being perfectly good must entail being good in all ways at all times and towards all other beings but there remain questions. First, what is the content of that goodness and second what is the relationship between that goodness and God?
As for the content of that moral goodness, there is quite a bit of disagreement among philosophers and theologians. Some have argued that the basic principle of that moral goodness is love, others have argued that it is justice, and so on. By and large, it seems that what a person believes to be the content and expression of Gods perfect moral goodness is highly, if not entirely, dependent upon the theological position and tradition that person is arguing from.
Some religious traditions focus upon Gods love, some focus upon Gods justice, some focus upon Gods mercy, and so on. There is no obvious and necessary reason for preferring any one of these to any other; each is as coherent and consistent as another and none rely upon empirical observations of God which would allow it to claim epistemological precedence.
Another understanding of the concept of omnibenevolence focuses upon a more literal reading of the word: a perfect and complete desire for goodness. Under this explanation of omnibenevolence, God always desires what is good, but that doesnt necessarily mean that God ever actually tries to actualize the good. This understanding of omnibenevolence is often used to counter arguments that evil is incompatible with a God which is omnibenevolent, omniscient, and omnipotent; however, it is unclear how and why a God who desires the good would not also work to actualize the good. It is also difficult to understand how we can label God as morally good when God desires the good and is capable of achieving good but doesnt bother to actually try.
When it comes to the question of what sort of relationship exists between God and moral goodness, most discussions are over whether goodness is an essential attribute of God. Many theologians and philosophers have tended to argue that God is indeed essentially good, which means that it is impossible for God either to will evil or to cause evil everything that God wills and everything that God does is, necessarily, good.
A few have argued contrary to the above that while God is good, God is still capable of doing evil. This argument attempts to preserve a broader understanding Gods omnipotence; more importantly, however, it makes Gods failure to do evil more laudable because that failure is due to a moral choice. If God does not do evil because God is incapable of doing evil, that would not seem to merit any praise or approval.
Another and perhaps more important debate over the relationship between moral goodness and God revolves around whether moral goodness is independent of or dependent upon God. If moral goodness is independent of God, then God does not define moral standards of behavior; rather, God has simply learned what they are and then communicates them to us.
Presumably, Gods perfection prevents him from incorrectly understanding what those standards should be and therefore we should always believe what God informs us of them. Nevertheless, their independence creates a curious alteration in how we understand the nature of God. If moral goodness exists independently of God, where did they come from? Are they, for example, co-eternal with God?
In contrast to this, some philosophers and theologians have argued that moral goodness is entirely dependent upon God. Thus, if something is good, it is only good because of God outside of God, moral standards simply do not exist. How this came to be so is itself a matter of debate. Are moral standards created by a specific action or declaration of God? Are they a feature of reality as created by God (much as mass and energy are)? There is also the problem that, in theory, raping children could suddenly become morally good if God wished it.
Is the notion of God as Omnibenevolent coherent and meaningful? Perhaps, but only if standards of moral goodness are independent of God and God is capable of doing evil. If God is incapable of doing evil, then to say that God is perfectly good simply means that God is perfectly capable of doing what God is logically restricted in doing a wholly uninteresting statement. Moreover, if standards of goodness are dependent upon God, then saying that God is good reduces to a tautology.