Jer 31. “Behold, days are coming," declares the LORD, "when I will make a new covenant with the house of Israel and with the house of Judah,
32. “not like the covenant which I made with their fathers in the day I took them by the hand to bring them out of the land of Egypt, My covenant which they broke, although I was a husband to them," declares the LORD.
33. "But this is the covenant which I will make with the house of Israel after those days," declares the LORD, I will put My law within them and on their heart I will write it; and I will be their God, and they shall be My people.
34. "They will not teach again, each man his neighbor and each man his brother, saying, 'Know the LORD,' for they will all know Me, from the least of them to the greatest of them," declares the LORD, "for I will forgive their iniquity, and their sin I will remember no more."
Of course we are not saved by the law (Eph 2:8). We know and are convinced it is by grace. Just like the Gentiles in Acts 15. But they grew in faith by hearing Moses and the prophets, acts (15:19-21). The law now takes it rightful place in the hearts of men because of the work of grace and we decide not to live a life of lawlessness as fruit of what G-d has done in our lives. We live in relationship to grace, not in obligation to the law. So as Rav Shaul put it "Should we sin so that grace may abound" (Rm 6:1). We have to make the distinction between living in grace with the law in our hearts and living in grace with a lawless attitude. There is a tension here that has to be worked out daily in our lives. I think that G-d allows this tension to keep us on our toes.
A man who runs stop signs is a law breaker. If a drunk knocks down the stop sign the (stop sign running) law breaker has been set free from the law. But the man who has concern for his neighbor says, even though the sign is down I will not run this corner where there used to be a stop sign because I am more concerned for my neighbor than my right to do as I please. This man now fulfills the law according to the interpretation of Yeshua, Mt 23:37-40.
So, the question we have to ask is who is the one who keeps the law, is it the one who has been set free from it because it is now in his heart or the one who is bound by it because it still resides on tablets of stone?