The Relevance of the Old Testament for the New Testament Believer
What relevance, if any, does the Old Testament have for the New Testament believer? That is not a question to be left to Bible scholars with little or no practical value for the “people in the pew.” It is of tremendous practical concern for the church and the individual Christian. Walter Kaiser Jr. states this very clearly,
It is no exaggeration to claim that this question outranks every other problem in Christian theology. The manner in which this question is solved affects every other area of theology in one way or another. Therefore, we can pose no more fundamental question in all of theology: the answer to this problem will leave its mark in every realm where we can formulate and act out our theology.
What is the relevance of the OT for the NT believer?
Jesus and the Old Testament
Jesus believed the OT was the Word of God. He always spoke of its historical accounts as true and reliable (Mt 12:40-41, Lk 17:26-27). But what did Jesus say concerning the relevance of the OT to the NT believer? Matthew 5:17-19 is a crucial passage where he answers this question. Jesus said,
Do not think that I came to abolish the Law or the Prophets. I did not come to abolish, but to fulfill. For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished. Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven. (NAS)
The first thing that needs to be established is what Jesus meant by the “Law or the Prophets.” There are various ways that the NT refers to the OT as a whole. Sometimes the whole of it is referred by the broad designation, “the Law.”’. On one occasion Jesus referred to the OT canon as “Moses and the Prophets.” Shortly thereafter, he referred to it as “the Law of Moses and the Prophets and the Psalms.” The “law and the prophets”, the terminology Jesus uses here, is also used as a designation of the OT.  In this particular instance, he says the “Law or the Prophets” and not the “law and the prophets”. The or may or may not be significant, but in either case, our Lord is clearly referring to the recognized and received canon we know as the OT. There are two things that our Lord says about his relationship to it. First, negatively, he declares what he did not come to do with respect to the OT. In the second place, he declares what he did come to do with respect to the OT.
What Jesus Did Not Come to Do
Jesus makes it abundantly plain what he did not come to do with respect to the Old Testament. He said, “Do not think that I came to abolish the Law or the Prophets “(Mt 5:17). One of the definitions of abolish in the original language is “do away with, abolish, annul, make invalid.” This definition seems to fit this context well. Jesus knew that he was about to drop a bomb on his hearers. That bomb is v.20. Jesus said, “For I say to you, that unless your righteousness surpasses that of the scribes and Pharisees, you will not enter the kingdom of heaven.” The people considered the Scribes and Pharisees to be the religious leaders of the day, the experts and enforcers of the Law respectively. Yet Jesus in no uncertain terms said that they were not going to enter the kingdom of heaven. Such a charge amounted to knocking the props out from under the popular understanding of Old Testament religion. It also would have made him appear as a zealous revolutionist “who had had come to undermine the Law.” Therefore, before he made such a shocking statement, he whole-heartedly declares in “V17-18 that everything He is going to teach is in absolute harmony with the entire teaching of the Old Testament Scriptures.”
Just that statement alone begins to lead us in the right direction when seeking to determine the relevance of the OT for the NT believer. The phrases, ‘I came’, and ‘I did not come’ in v. 17 are two ways Jesus spoke of his having come from heaven to earth to accomplish the saving mission given to Him by his Father (Jn 6:32-40). This means that his mission to save sinners and usher in the kingdom will not render the OT obsolete. That should make anyone cautious and think twice before declaring that any aspect of OT revelation is not relevant for the NT believer.
What Jesus Came to Do
Since he did not come to destroy the ‘Law or the Prophets’, what exactly did he come to do in regards to the Old Testament? “I did not come to destroy but to fulfill” (Matt 5:17b). When dealing with this passage, there are two things on which most professing evangelicals are in agreement. We agree that Christ came to fulfill the OT prophecies concerning the Messiah (1 Pet 1:10-11). We also agree that he came to fulfill the many types and shadows that find their fulfillment in Him (Col 2:16-17; He 10:1-2). To take any other position would amount to a denial of the Christian faith. The central truth of the NT is that Jesus of Nazareth is the Messiah promised in the OT scriptures starting all the way back in Genesis 3:15 (Ro 1:2-4). Beyond that there is unity among evangelicals in the belief that there yet remains revelation in the OT concerning Christ that still awaits fulfillment. It seems that v.18 has direct application to that. “For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished.” The word translated fulfill in v.18 is not the same as in v.17. One of its possible usages that best fit this context is, “to be done, performed, effected”. The passing away of heaven and earth is no doubt a reference to the second coming when our Lord returns in glory ushering in a New Heavens and New Earth. Evangelicals agree that the OT will remain authoritative, and thus relevant concerning all its predictions concerning Christ culminating in that last great event predicted in the OT, the Day of the Lord.
However, here is where the agreement ends and the division begins among evangelicals. The division is over this question: How does Jesus Christ fulfill the ethical demands of the OT? That is the real focus of Jesus’ concern in this text. Consider three things which confirm that this his focus. First, Jesus’ used of the phrase ‘the Law or (and) the Prophets’ at times with a narrower sphere of reference-the entirety of the ethical demands revealed in OT and summed up in the two great commandments (Mat 7:12; Mat 22:34-40). Second, we must keep in mind the context of the entire sermon when seeking to interpret this passage. Nowhere in the sermon did Christ address or expound OT prophesies/types. He expounded the ethical standards that are to be practiced by the genuine members of the kingdom of heaven revealed in the Law and the Prophets (Mt 7:12). Third, what puts it beyond any doubt that the ethical demands of the OT is Jesus’ focus is what he said in v.19, “Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven.”
So, in what way did Jesus come to fulfill the ethical demands of the OT? That is what we will consider in the next blog post.
 The abbreviations OT and NT will be used throughout the remainder of these blog posts.
 Walter Kaiser, Toward Rediscovering The Old Testament (Grand Rapids: Zondervan Publishing House, 1991), 9.
 New American Standard Version.
 1 Cor. 14:34; Jn 10:34-35
 Lk. 24:27
 Lk. 24:45
 Ro. 3:21
 Walter Bauer, A Greek-English Lexicon of the New Testament and other Early Christian Literature (Chicago: The University of Chicago Press 1979), 414
 William Hendrickson, Exposition of the Gospel According to Matthew, in New Testament Commentary (Grand Rapids: Baker Book House, 1973), 288
 Martyn Lloyd Jones, Studies in the Sermon on the Mount (Grand Rapids: Eerdmans, 1989), 181
 Walter Bauer, A Greek-English Lexicon of the New Testament and other Early Christian Literature (Chicago: The University of Chicago Press 1979), 80.