The Bible is meant to be picked up and read, but the reading of any book requires a basic understanding of how language is used. Some understanding is pretty basic. No one confuses the statement “I love you with all my heart” with the muscular organ that pumps our blood.
Some understanding is not so readily apparent. The special status of the Bible as God’s revelation to humanity deserves that we give heed to these things. The New Testament clarifies the Old Testament. People go astray when they find meaning, for instance, in Old Testament prophecies that the New Testament does not teach or, even more so, contradicts. I’m not saying that the New Testament contradicts the Old Testament. I’m saying that the New Testament contradicts the reader’s understanding of that Old Testament passage.
Having said that, Reformed Baptists are not “New Testament Christians” if that term discounts the importance of the Old Testament. Indeed, understanding the Old Testament is necessary for one to comprehend the New Testament. A simple illustration reveals this. Paul writes: “Therefore, just as sin came into the world through one man, and death through sin, and so death spread to all men because all sinned—for sin indeed was in the world before the law was given, but sin is not counted where there is no law. Yet death reigned from Adam to Moses, even over those whose sinning was not like the transgression of Adam, who was a type of the one who was to come” (Romans 5:12–14). Our understanding would be really impoverished had we not studied the first five books of the Old Testament.
Understanding the Old Testament in light of the New Testament, we must recognize the continuity and discontinuity of the two testaments. Some things remain the same throughout both testaments, and yet some things indeed change.
From Genesis through Revelation, the Bible teaches that there in only one way of salvation. This illustrates the continuity of the Scriptures. In Genesis 3:15 we find what is often called the protoevangelium, the “first gospel”: “I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel” (Genesis 3:15). Speaking to Satan who inhabited the body of a serpent, God declared that the devil and his offspring would always be the enemy of the Messiah and those who follow him, but the devil would be defeated by the One who represented “her offspring”: “he shall bruise your head.”
How do we come to the understanding of the identity of the One who defeated Satan? It is through the New Testament. Examine Hebrews 2:14-15: “Since therefore the children share in flesh and blood, he himself likewise partook of the same things, that through death he might destroy the one who has the power of death, that is, the devil, and deliver all those who through fear of death were subject to lifelong slavery” (see also Romans 5:12–19, 16:20, and 1 Corinthians 15:45-49).
Nothing changes as far as salvation is concerned from Genesis to Revelation. It has always been and will always be by God’s grace through faith in the promised Messiah. Genesis 15:6 states that Abraham “believed the Lord, and he counted it to him as righteousness.” Paul comments on this in Romans 4:1-3: “What then shall we say was gained by Abraham, our forefather according to the flesh? For if Abraham was justified by works, he has something to boast about, but not before God. For what does the Scripture say? ‘Abraham believed God, and it was counted to him as righteousness.’”
Not only is there continuity between the testaments, but there is also discontinuity. While there has always been only one “true Israel,” those who by faith believe in the Messiah, there were practices prescribed in the Old Testament that are no longer in place since the crucifixion and resurrection of Christ. The Old Testament sacrificial system has been fulfilled in Jesus (see Hebrews 9-10). The ethnic people of God, the Jews, were governed by civil law that are no longer in place for the people of God. Paul writes in Romans 13:1, “Let every person be subject to the governing authorities. For there is no authority except from God, and those that exist have been instituted by God.” Jesus declared in John 18:36: “My kingdom is not of this world. If my kingdom were of this world, my servants would have been fighting, that I might not be delivered over to the Jews. But my kingdom is not from the world.”
Discontinuity is seen in the sign given to distinguish the people of God. In the Old Testament, that sign was circumcision and was for males only. The people of God were to be known as separated unto God, with circumcision signifying that their hearts had nothing between them and God. To reject circumcision was to reject God’s covenant with Israel (Genesis 17:7-14, Deuteronomy 10:16; 30:6; Romans 2:25-29). In the New Testament, however, that sign has been replaced with baptism, a sign not for an ethnic people but for believers only and given to both male and female (Matthew 28:19; Romans 6:3-4; Colossians 2:9-15).
The Old Testament is essential to an understanding of the New Testament, but it is not the Old Testament that clarifies the New Testament. Rather, it is the other way around. As Augustine declared: “The New is in the Old concealed; the Old is in the New revealed.” It is through the New Testament that we truly understand the Old Testament, finding both continuity and discontinuity between the testaments.