Is God under His Own Law?

As far as the Law goes, yes, God does keep the Law because the Law is a reflection of his character. However, we have to be careful when we begin to apply this idea because the particular manifestations of God's character in actual laws only properly reflect his character when understood in their original contexts. To know how to apply the various laws today, we need to figure out what aspect of God's character the laws reflected, and then to figure out what a proper reflection of that aspect would be today. For example, now that Jesus has come, it is not an appropriate reflection of God's character for us offer animal sacrifices as atonements for sin. Every time we seek to apply a law today, we need to take into account things like changes in redemptive history, changes in culture (some laws are culturally conditioned), and personal changes (e.g. the way I express love for God may be different from the way you do). Figuring out what we have in common with the original audience and its historical/cultural/personal settings helps us know how to apply the laws today, but knowing where our settings differ from those of the original audience is also important.

That being said, we also need to recognize the historical/cultural/personal similarities and differences between God in his settings and us in ours. When it comes to the "do unto others" idea, there are certainly some ways in which God treats us as he would have us treat him. For example, he always deals justly and fairly with us, and he wants us to deal justly and fairly with him (e.g. we ought not to grumble against him as if he had treated us wrongly). On the other hand, God does not want us to become his judge as he is our judge. There is a significant personal difference between us and God that prohibits us from applying the principle in a way that would make us his equals or superiors.

This approach does make applying the Law quite a bit more difficult than just following the rules as we find them in the Bible. Even though God took great care to demonstrate his character to us in the Bible, and to write out his Law for us, it still takes wisdom to know the right thing to do in any particular situation. We can't just "paint by numbers." Rather, we have to consider everything we know about God, about ourselves, about redemptive history, about the world and culture, and about many other things, and from that we have to determine what God would have us do. Sometimes this is pretty easy, such as the answer to the question "Should I kill the store clerk and steal a lotto ticket because I'm greedy?" At other times, though, it can be very hard to know the right answer, such as the answer to the question "When it is okay to lie?"

One reason this issue can be very important is that people sometimes argue that God is the best example for us to emulate when it comes to keeping his Law. That is, some argue that if God executes vengeance, then we ought to do so also. But God's Word makes it clear that vengeance ultimately belongs to God alone (e.g. Rom. 12:19), and that humans may only engage in it when God delegates his authority to them (e.g. Rom. 13:1-4). Thus, we must understand not only how people are obligated to obey the commandments, but also how God's observance of the principle of the commandments may differ radically from our own.