Can God Make A Rock So Big He Can't Lift It?

My friend Anne asked me this question regarding Thomas Aquinas' ideas on the law of non-contradiction,
"What do you think of his ideas on the law of non-contradiction? He believes that it is reasonable to believe that God is incapable of doing anything contrary to reason or his own personality (i.e. a square circle)...I can see some logic in this, but it seems to remove God's omnipotence."

Well I think what he means.. for instance.. to answer that argument "Can God make a rock so big he can't lift it?" It's just silly.. people may say "God can do anything." But then one might ask, "Can God sin?" of course not! Therefore, he can't possibly do anything that contradicts his nature or character.

Aquinas uses the term "natural law" to refer to morality, or the moral law. He sees law as a rational attempt to guide action. A law is a prescription that we act or not act; it may also exist in us as an inclination to act in certain ways. Sin is only born thru man--a violation of God's law. God has the supreme authority above all things--an omnipotent being. He is the rule maker and infinite being.

The first principles of natural law are self-evident truths. In this they resemble the first principles of speculative reason (such as the law of non-contradiction).

Law requires that we act in accord with reason. The first principles of the natural law are "Good is what all things seek after" and "Good is to be done and promoted, and evil is to be avoided." So whatever practical reason naturally apprehends as our good (or evil) is to be done (or avoided).

Aristotle says that without the principle of non-contradiction we could not know anything that we do know. Presumably, we could not distinctly separate the subject matter of any of the special sciences, for example, biology or mathematics, and we would not be able to distinguish between what something is, for example a human being or a rabbit, and what it is like, for example pale or white. Aristotle's own distinction between essence and accident would be impossible to draw, and the inability to draw distinctions in general would make rational discussion impossible. According to Aristotle, the principle of non-contradiction is a principle of scientific inquiry, reasoning and communication that we cannot do without.

John 1:1, "In the beginning was logos (Greek logic), and the logic was with God, and the logic was God." God is logic. He is why we are able to reason with each other and have logical conclusions. God is incapable of doing what is against himself. This doesn't take away from his omnipotence, because it's not part of his character. God has never lied and never broken a promise. He would not break a promise because it would be against his character. What I mean by this is that he can't do wrong.. he can't go against his own will and character. Doing wrong is not part of him. It therefore cannot be removed from him because it never existed with him. Sin exists only with man. God can't even be in presence of what is wrong. He is good. He is what is right. We are the only ones capable of doing wrong.

It is not possible that something be both true and not true at the same time and in the same context. I think the notion of time is more inherent in the Law as we normally understand it, but that the notion of context is equally important. God cannot be both good and evil. Therefore, God is above contradiction.

It's difficult for me to grasp the idea of how mighty God is. To understand His supremeness and authority is beyond what we know. But we are capable of knowing just enough about his omnipotence that we understand man's place in the universe.