“Looking back now to the wealthy man who came to Jesus and asked, “Good Teacher, what must I do to inherit eternal life?” (Mark 10:17), how does the keeping of the law fit into Jesus’ answer? Jesus’ first answer to the man was, “If you would enter life, keep the commandments” (Matt. 19:17). We have seen that even though commandment-keeping will never provide a righteousness good enough to gain acceptance with God, nevertheless, the effort to do God’s will is essential. The question now is, is God’s will today expressed in the Old Testament law? A simple yes would be misleading. And a simple no would be misleading. Rather we must say something like: Yes, provided the law is filtered through the sieve of all the changes brought about by Jesus, who is the goal and fulfillment of the law.
“Jesus said, “Everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled” (Luke 24: 44). The Law and the Prophets were all aiming toward Jesus. Not surprisingly, when he came they would be fulfilled and changed. Jesus spoke about this change carefully and respectfully: “Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished” (Matt. 5:17-18).
“Abolition is not Jesus’ purpose. Fulfillment is. And when the law is fulfilled in Jesus, its original use changes dramatically. A new era has dawned, and Jesus’ followers will relate to the law differently than Israel did. That’s why Jesus said, “The Law and the Prophets were until John [the Baptist]; since then the good
news of the kingdom of God is preached, and everyone forces his way into it” (Luke 16:16).” — John Piper, “What Jesus Demands from the World“, pp. 162-163
(HT: The Vossed World)