The first reason we will consider is:
He came to Fulfil Scripture
“Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfil” (Matthew 5:17).
Matthew’s Gospel contains one of the most famous Bible passages, the Sermon on the Mount. In it the Lord Jesus first announced the blessedness of all true believers and then began to speak about His relationship to the Old Testament.
The Old Testament (“the Law and the Prophets”) was completed about 400 years before Jesus came and the Jews to whom He spoke regarded it as God’s Word. As He spoke about the Old Testament, Jesus wanted His audience to know that He had not come to “destroy” it. He hadn’t come to render it obsolete or invalid or to repeal its authority. Rather He had come to “fulfil” it. In His teachings, and in His life, death, and resurrection, Jesus is the true fulfilment of all the Old Testament anticipated.
To fulfil God’s law He would first teach that mere external obedience to God’s commands was not all God wanted. God’s desire for us is a deeper, genuine goodness. When God forbad murder His goal was that we would not hate. When God forbad adultery His aim was that we would not lust. Jesus filled up God’s commandments by interpreting them according to God’s character. He showed that they were far more challenging than many thought.
However, He did not stop at only teaching this; He showed it in His own life. He was, morally, the fulfilment of all the Law demanded. He loved God with all of His heart and soul and mind and He loved His neighbour as Himself (see Matthew 22:36-40). The law was fulfilled in Jesus’ life of moral perfection.
Not only so but He bore the judgment of the Law in His death. To be right with God by law-keeping we would need to keep God’s law continually and completely. We haven’t done this which means we are guilty before God and deserve His punishment. But Christ has “redeemed us from the curse of the law” (Galatians 3:13). How? By becoming a “curse for us”. He endured the punishment for our law-breaking on the cross.
Jesus came to fulfil the Law. He did this by teaching what the Law truly demanded, by living a life of moral perfection, and by dying as the substitute for sinners.
He also came to fulfil the Prophets. Many Old Testament predictions were fulfilled in His first coming. Details of His unique birth, perfect life, sacrificial death, and victorious resurrection were inscribed in writings originating hundreds of years prior to the events they predicted.
Before His crucifixion Jesus was betrayed by Judas Iscariot. A great crowd came to arrest Him in the Garden of Gethsemane. Peter thought he would defend his Lord by taking out his sword to fight against the crowd. Jesus said, “Put your sword in its place … do you think that I cannot now pray to My Father, and He will provide Me with more than twelve legions of angels? How then could the Scriptures be fulfilled, that it must happen thus?” (Matthew 26:52-54).
The Lord Jesus had come to fulfil scripture and He was determined to accomplish that mission. It was only after He knew that “all things were now accomplished” that He said, “It is finished!” and, “bowing His head . . . gave up His spirit” (John 19:28-30).
We should be thankful that Jesus came to fulfil Scripture. In His teaching, and by His life, we learn that we could never be right with God by attempting to keep His commandments. And, because of His sacrificial death, we see that we don’t have to, for “Christ died for our sins according to the Scriptures and . . . rose again the third day according to the Scriptures” (1 Corinthians 15:3-4).