The distinction between law and grace has been part of Christianity practically since it first began. The heart of the gospel is that it is God’s grace, and not the Law, that saves us. We can’t establish a right relationship with God by keeping His commands because none of us keeps those commands perfectly. So God chose to act, becoming human in the person of Jesus and dying for us so that our sins could be forgiven and we could become children of God.
Some Christians have an unfortunate tendency to associate the Law that cannot save us with the Old Testament and grace with the New Testament. This makes the Old Testament little more than an obsolete relic of an age without grace when people struggled to be obedient enough to save themselves, proof of the problem Christ came to solve. Or it becomes a collection of inspiring stories about heroes who can serve as models for faith and good behavior. Now, the Old Testament does show us humanity’s desperate need, and it does give us role models and moral instruction, but it’s more than that. It’s the oldest record we have of God’s grace.
Yes, I said the Old Testament records grace. And to illustrate this I’m going to turn to Exodus20, the chapter that contains the Ten Commandments. This chapter is one of the clearest, most concise statements of God’s law. But notice the first thing God says in it: “I am the LORD your God who brought you out of the land of Egypt, out of the house of slavery” (Ex 20:2). Before God commands the Israelites to do anything, He points out what He has already done. The Exodus was the defining event of Israel’s history. It made Israel a nation, brought liberty to its people and demonstrated dramatically that God had chosen them and was willing and able to overcome anything that opposed them. It was the moment that fulfilled God’s promise to Abraham, when He swore to make Abraham’s descendants a great nation. And God did all this when Israel was helpless. They had done nothing to deserve God’s favor, nothing to merit being rescued. The Exodus was pure grace.
And so, God begins the Law with a reminder of grace. It is because the LORD is their God and has established a unique relationship with them through the Exodus, that they are to worship no other gods, to refrain from making idols, to respect God’s name and so on. Even the laws relating to relationships with other people reflect the fact that these are people made in God’s image, so the way they relate to each other reveals their attitude toward God.
The Law is rooted and grounded in grace. Even at the beginning, when God first revealed it to Israel, He began by pointing out the grace they had already received. And so it is with us. The New Testament has much to say about how we ought to live, and the moral laws within the Old Testament are still binding on Christians (though ceremonial laws and stipulations about Israel’s government are not). If we have truly received God’s grace, we must obey God’s law, and if we appreciate God’s grace we will want to. But we must never let law become prior to grace. As with Israel, so with us: God saves first, and obedience is a response to that.