A Christian who reads the New Testament apart from the Old Testament loses the framework needed to understand it. The gospel stands on a long history of God’s revelation. Christ came as the fulfillment of what God had already spoken, not as the founder of a new religious vocabulary. The New Testament rests on the Old at every point, and Christ is misread when that foundation is ignored.
Christ Reveals Himself Through the Old Testament
After His resurrection, Jesus grounded His disciples in the Scriptures they already had and revealed how those writings spoke of Him.
Luke records that Jesus rebuked the disciples for being slow of heart and then explained “the things concerning Himself in all the Scriptures,” beginning with Moses and the Prophets (Luke 24:25–27). Christ taught that He could not be known rightly apart from the Old Testament.
Jesus said the same to the religious leaders in John 5. They searched the Scriptures, believing they had life in them, yet they refused to come to Him. Christ declared that those Scriptures testified about Him and that Moses himself accused them (John 5:39–47). Jesus treated the Old Testament as the witness that revealed who He is.
In the Sermon on the Mount, Jesus affirmed the permanence and authority of the Law and the Prophets. He came to fulfill them, not to discard them. He declared that obedience and teaching must flow from what God had already spoken (Matthew 5:17–19). Christ acted in full continuity with the mission revealed in the Old Testament.
The Apostles Preached the Gospel From the Old Testament
The apostles proclaimed the gospel as the fulfillment of God’s prior revelation. Paul taught that the Scriptures were written for the instruction of the church so that believers would possess endurance and hope (Romans 15:4). When Paul spoke of Scripture, he was referring to the writings God had already given, what we now call the Old Testament.
Paul also told Timothy that the sacred writings were able to give wisdom that leads to salvation through faith in Christ Jesus (2 Timothy 3:15–17). Timothy learned those writings long before the New Testament existed. The Old Testament formed the categories by which he understood sin, righteousness, judgment, and redemption.
The book of Hebrews makes this dependence unmistakable. Christ’s priesthood, sacrifice, covenant mediation, and kingship are explained entirely through Old Testament categories. Without the tabernacle, the sacrificial system, the promises to David, and the covenant structure revealed through Moses, Hebrews becomes unintelligible.
The Cost of Neglecting the Old Testament
When the Old Testament is sidelined, the gospel is reduced. Sin becomes personal failure rather than covenant rebellion. Grace is reduced to emotion instead of mercy granted to those who stand guilty before God. Repentance loses its weight. Obedience becomes optional. Judgment is softened. Christ’s kingship is diminished.
The Old Testament reveals the holiness of God, the seriousness of sin, the necessity of blood atonement, and the nature of covenant faithfulness. These truths are assumed throughout the New Testament. Without them, Christ is reshaped into a figure who saves without reigning and forgives without demanding obedience.
This is not a call to place Christians under the Mosaic covenant. It is a call to receive the whole counsel of God as unified revelation. The law reveals God’s character. The prophets proclaim His purposes. The writings shape wisdom and fear of the Lord. Christ fulfills all of it and cannot be known apart from it.
Semper Reformanda
Objection: The Old Testament belonged to Israel, not the church.
Response: Jesus, the apostles, and the early church treated the Old Testament as Christian Scripture. Christ taught from it. The apostles preached from it. The church was formed by it. Covenant distinctions remain, but continuity is real. The same God speaks, the same holiness stands, and the same redemptive purpose unfolds in Christ.
Objection: “The New Testament reveals Christ clearly, so the Old Testament is no longer necessary.”
Response: The New Testament itself denies this claim. Jesus told the Jews that Moses wrote about Him and that refusing Moses made belief in Him impossible (John 5:46–47). After His resurrection, He rebuked His disciples for failing to understand what the prophets had spoken and then explained His suffering and glory from Moses and the Prophets (Luke 24:25–27). The clarity of Christ in the New Testament depends on the categories supplied by the Old. Sacrifice, priesthood, covenant, kingdom, and judgment are not explained anew. They are assumed. The New Testament reveals Christ as the fulfillment of what was already spoken, not as a replacement for it.
Objection: “The Old Testament law brings bondage, while the New Testament brings freedom.”
Response: Scripture defines freedom differently than modern assumptions. Paul teaches that the law is holy, righteous, and good, and that sin uses the law to produce death, not that the law itself enslaves (Romans 7:12–13). The problem is not God’s law but the sinful heart. Freedom in Christ is freedom from condemnation and from slavery to sin, not freedom from obedience. The Old Testament reveals the character of God, the nature of holiness, and the seriousness of rebellion. Without these, grace is misunderstood and freedom becomes license. The apostles consistently used the Old Testament to instruct believers in obedience, endurance, and hope (Romans 15:4), showing that freedom grows from truth, not from forgetting God’s prior revelation.
Truth That Withstands
Christ is revealed through Moses and the Prophets. The gospel stands on the foundation God laid long before the incarnation. When the Old Testament is neglected, the church loses its bearings and the gospel loses its depth. Faithfulness requires the whole Word of God, received as one unified testimony to Christ.
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