A question in the Church today is what is the relationship between the Old and New Testaments of the Bible. There are many in the Church today who believe the Old Testament has nothing to say to the Christian or that there are somehow two different Gods described in the two testaments; the angry, judgmental God of the OT as compared to the merciful, loving God of the NT. This view has at its foundation a misunderstanding of grace and a low view of the holiness of God where man is somehow equipped to judge God. The Bible reveals one God whose character remains the same. Hebrews 13:8 says,
8 Jesus Christ the same yesterday, and to day, and for ever.
The Old Testament reveals the character of both God and man. It shows God as holy and loving. The Old Testament reveals the Law of God and shows man continually falling short of its demands. The Old Testament shows man’s need for a Savior and makes many promises that point to the coming of Christ. The Old Testament provides a record of the history of the nation that God chose for Himself, the nation of Israel. Within the history of the nation of Israel, God showed His design for civil government and His design for the family.
The main purpose of the Old Testament is to point to the Lord Jesus as the coming Messiah who would be Prophet, Priest, and King.
The New Testament lifts up Jesus as the fulfillment of the Old Testament. He is the fulfillment of the Law. Not only did He keep the moral law perfectly but Jesus is the reason for the ceremonial law. The many sacrifices and feasts of the Old Testament all point to something in the person or work of Jesus Christ. The New Testament looks back and explains (interprets) how Jesus fulfills the Law and the many promises God has made.
Jesus is the fulfillment of the message of the Old Testament prophets. They preached man’s rebellion, the need for repentance, God’s judgment, and God’s restoration. The New Testament begins with four Gospel accounts describing the person and work of the Lord Jesus Christ. The Gospels continually quote the Old Testament and show Jesus as their fulfillment.
The main purpose of the epistles of the New Testament are to explain the mystery of the Church in light of Christ’s redeeming work. The epistles of the New Testament have a general common structure. The first part of the epistles describe what is now true about the Church because of the person and work of Jesus Christ. The second part of each epistle tells members of Christ’s Church because these things are true, now live this way (see Ephesians 1-3, orthodoxy and Ephesians 4-6, orthopraxy).
The Revelation of Jesus Christ sums up the Old Testament and New Testament prophecies concerning the second coming of Jesus Christ, the Millennium, and the New Heavens and New Earth. Revelation allows the Christian to apply prophetic passages correctly from both testaments. It is very fitting that the last book of the Bible is the Revelation of Jesus Christ for that is the purpose of the entire Bible; to reveal the Lord Jesus Christ to a world that desperately needs Him.