(This is adapted from a comment I made in response to Bruce Nielson’s post titled “The Laws of Physics and the Comprehensibility of God“. Someone who’s more philosophically literate than I might want to correct my terminology, but I hope the reasoning at least is sound.)
I believe you are saying that something is incomprehensible unless explainable by laws, which is another way of saying, governed by laws by which it may be explained. By “explained” I take you to mean how the thing exists and how it acts as it does. [Bruce had argued that God is incomprehensible, not only to us but also to himself, unless he is explainable by "laws". This is part of his idea that "physics" is the study of all of reality, theoretically including God, angels, spirits, etc., and not just what we currently conceive of as "physical" reality. See his post for further details.]
I think laws can be divided into two kinds: (A) Those which govern non-rational things, and (B) those which govern rational beings.
Laws of type A govern non-rational things insofar as they are purely non-rational. Thus the law of gravity governs my body but has no direct effect on my thoughts. Type A laws govern things such as atoms, molecules, energy, light, etc. Things governed by such laws have no choice but to obey them. I will call laws of this type non-rational laws.
Laws of type B govern rational beings insofar as they are purely rational. Type B laws govern how rational beings are to conduct themselves, or in other words what we call the moral law. The moral law governs my spirit, i.e. my intellect and my will, but has no direct effect on my body. I can choose whether or not to obey the moral law. I will call a law of this type a rational law.
Non-rational laws govern how non-rational things interact with each other, for example how energy interacts with matter, how a rock interacts with the earth, etc. Rational laws govern how rational beings interact with each other, in other words how they treat each other and whether or not they obey the will of the supreme rational being we call God.
I say that God is not subject to non-rational laws since he is purely rational. No part of him is non-rational, such that it should be affected by laws governing the interaction of non-rational things insofar as they are purely non-rational.
I say that God is not subject to rational laws, since they are equivalent to God’s own will — in other words, to obey the moral law is to obey God’s will. The written moral commandments are the expression of God’s will as it concerns our behavior: He wills that we not steal or commit adultery, etc., therefore those things are a violation of the moral law. God is not subject to rational laws since he is their author: To say he is subject to them would be to say he is subject to himself, which is just another way of saying he is subject to no one.
There is no source of any laws outside God: He invented non-rational laws when he created non-rational things, and rational laws are nothing more than his will concerning the behavior of rational beings.
God is what you would call a “brute fact”, if by that term you mean a thing which has no external cause of its existence or behavior. By that definition he is the only brute fact, or what we Catholics call the Uncaused Cause. Other spirits are not brute facts since they have, and are therefore explainable by, a cause other than themselves, namely God. Such spirits are not subject to non-rational laws since they are purely rational (and therefore have no parts that are purely non-rational). However they are subject to rational laws since they are subject to the moral law, i.e. God’s will.
Human beings are subject to both non-rational laws and rational laws, since they are a composite of non-rational and rational (the only composite beings, in this sense, that we know of): Their bodies are subject to non-rational laws, while their spirits are subject to rational laws.