Q: What did God at first reveal to man for the rule of his obedience?
A: The rule which God revealed at first to man for his obedience was the moral law.
Romans 10:5 For Moses writes about the righteousness that is based on the law, that the person who does the commandments shall live by them.
Now we're getting into the meat of God's holy and good law. Again, I remind us of our path up til this point. We've already talked about the Fall and mankind's depravity. We already know that we cannot earn our salvation by keeping the law of God. We've also talked about God's gracious act of election, justification, and sanctification. Remember, with sanctification, we talked about the indicatives and imperatives in Scripture. We have the promises of what God has already done and will do for us, and then the imperatives of how we are to act and live in light of those great truths. The indicatives empower the imperatives. You can re-read the post on sanctification here if you need a refresher. It's in this light that we're now talking about obeying the law of God.
Because of what God has done for us through the life, death, resurrection, and glorification of Jesus Christ, God's law no longer becomes a burden for us, but rather, a delight. We should delight in and strive to keep the law of God so that we can live lives that are a sacrifice of praise.
God did not leave us without clear moral direction. The "moral law" of God that the catechism refers to here is, as we'll see next week, summarized in the ten commandments. So as we move forward the next couple of weeks, the catechism is going to begin unpacking the ten commandments with the hope that we as God's people would truly come to understand and love God's holy law. But as we go forward with this, again, I want to remind us that we do not keep the law in order to earn our salvation, but rather, we strive to keep the law because of our election, justification, adoption, sanctification, and glorification! If we want to avoid the trappings of legalism, if we want to avoid slipping into a works-based salvation, we must keep this distinction in mind. If we do not keep this distinction, God's law will become a burden to us. Jesus Christ has removed that burden from us, so let's not place it back on our necks!