Make sure you have a notebook and pen on hand for writing down your thoughts as you study this lesson. Remember you can double-click any word for a quick definition and pronunciation.

Objective

In this lesson we’ll see that the Old Testament is incomplete without the New Testament, and discover how Jesus fulfills God’s promises, perfects the law, and brings salvation to all nations.

Key Verse

Matthew 5:17: [Jesus is speaking:] Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them.

Introduction

Between the close of the Old Testament and the opening of the New Testament, four hundred years passed without any prophetic word from God. This period is sometimes called the “silent years,” when no inspired Scripture was written and no prophet arose to speak God’s message. Yet during this time, God was still at work, preparing the world for the coming of the Messiah. The Persian Empire gave way to the Greeks, who spread a common language across the known world. Then the Romans built roads and established peace, making travel safer than it had ever been. All of this was part of God’s perfect timing for the arrival of His Son.

When Jesus finally came, He made a remarkable statement about His relationship to the Old Testament. He declared that He had not come to destroy the law or the prophets, but to fulfill them. This means that Jesus is the completion and culmination of everything God had been doing throughout Israel’s long history. He is the answer to every promise, the fulfillment of every prophecy, and the reality to which every shadow pointed.

We cannot truly understand who Christ is without the Old Testament. When we read that Jesus is the Son of Abraham, the Son of David, the Messiah, or the Lamb of God, these titles mean nothing to us unless we know the Old Testament stories and promises that give them meaning. The New Testament assumes that we are familiar with the Old Testament scriptures, because it constantly quotes them, refers to them, and builds upon them.

In this lesson, we’ll explore three crucial ways that the New Testament completes the Old Testament—three ways that Jesus fulfills the law:

• Promise and fulfillment
• Law and grace
• Israel and the Gentiles

Promise and Fulfillment

The New Testament gives us the fulfillment of the promises of the Old Testament. From the very beginning of Genesis, God had been making promises about how He would redeem His creation and restore His relationship with humanity. These promises began in the garden of Eden when God told the serpent that the seed of the woman would crush his head. They continued through God’s covenant with Abraham, promising that through his offspring all nations would be blessed. They grew more specific through God’s covenant with David, promising an eternal throne and kingdom.

Throughout the Old Testament, God gradually revealed more and more about His plan of salvation. This process is sometimes called progressive revelation—like a sunrise that begins with just a hint of light on the horizon and gradually grows brighter and brighter until the full glory of the sun floods the sky. In the same way, God’s plan of salvation started with simple promises and shadows, then grew clearer through the law and the prophets, until finally the full light of truth shone forth in Jesus Christ.

Proverbs 4:18: The path of the righteous is like the morning sun, shining ever brighter till the full light of day.

The prophets spoke of a coming Messiah who would deliver God’s people and establish His kingdom. They described His birth, His ministry, His suffering, and His glory. But they didn’t always understand how all these prophecies would fit together. Sometimes they saw the Messiah as a suffering servant, rejected and despised. Other times they saw Him as a conquering king, ruling over all nations. They couldn’t fully grasp that these were not contradictory visions, but rather two different phases of the Messiah’s work.

This was the mystery that remained hidden until the New Testament revealed it clearly: the Messiah would come not once, but twice. In His first coming, Jesus came as the suffering servant to die for our sins. In His second coming, He will return as the conquering king to establish His eternal kingdom. The prophets saw these two events as if they were looking at two mountain peaks in the distance—from their perspective, the peaks seemed close together, but in reality there is a great valley of time between them.

1 Peter 1:10-12: Concerning this salvation, the prophets, who spoke of the grace that was to come to you, searched intently and with the greatest care, trying to find out the time and circumstances to which the Spirit of Christ in them was pointing when he predicted the sufferings of the Messiah and the glories that would follow. It was revealed to them that they were not serving themselves but you, when they spoke of the things that have now been told you by those who have preached the gospel to you by the Holy Spirit sent from heaven. Even angels long to look into these things.

(Notebook Moment: Think about how the Old Testament believers trusted God’s promises even though they didn’t fully understand how or when they would be fulfilled. How does this encourage you to trust God’s promises for your own life, even when you can’t see how everything will work out?)

Jesus Himself declared that the entire Old Testament pointed to Him. After His resurrection, He appeared to two disciples on the road to Emmaus and explained how all the Scriptures testified about Him:

Luke 24:25-27: He said to them, ‘How foolish you are, and how slow to believe all that the prophets have spoken! Did not the Messiah have to suffer these things and then enter his glory?’ And beginning with Moses and all the Prophets, he explained to them what was said in all the Scriptures concerning himself.

Law and Grace

The second way Jesus fulfills the Old Testament is by bringing the reality of grace that the law could only point toward. The law given through Moses was never meant to be the final answer to humanity’s sin problem. God never intended for people to be saved by perfectly keeping all the commandments—this would be impossible for sinful human beings. Instead, the law served several important purposes in God’s plan.

First, the law revealed God’s holy character and His righteous standards. It showed people what God required and how far they fell short of His glory. Second, the law acted as a guardian or schoolmaster, protecting God’s people and teaching them about sin until Christ came. Third, the law pointed forward to the grace that would come through Jesus, showing through its sacrifices and ceremonies that forgiveness required the shedding of blood.

Even in the Old Testament, God made it clear that He was more concerned about the heart than about mere external obedience to rules. When Moses gave the law to Israel, he emphasized that true obedience came from loving God with all your heart, soul, and strength:

Deuteronomy 6:5-6: Love the Lord your God with all your heart and with all your soul and with all your strength. These commandments that I give you today are to be on your hearts.

But the people struggled to keep this focus on the heart. Over time, many became more concerned with following rules than with truly loving God. By the time Jesus came, the religious leaders had added hundreds of additional rules to God’s law, creating a burden that no one could bear. They tithed even the smallest garden herbs but neglected justice, mercy, and faithfulness. They kept the Sabbath meticulously but missed its true meaning. Jesus confronted this legalistic approach again and again, showing that the law was meant to lead people to love God and love others, not to become a source of pride or a way to earn God’s favor.

The prophet Ezekiel looked forward to a time when God would transform people’s hearts from within, rather than merely giving them external commands:

Ezekiel 36:26-27: I will give you a new heart and put a new spirit in you; I will remove from you your heart of stone and give you a heart of flesh. And I will put my Spirit in you and move you to follow my decrees and be careful to keep my laws.

This is exactly what Jesus came to do. Through His death and resurrection, He made it possible for God’s Spirit to live in every believer, writing God’s law on our hearts and giving us the power to obey from the inside out. This is the New Covenant that Jeremiah prophesied about, where God’s law would be internal rather than external, written on hearts of flesh rather than tablets of stone.

The early church had to wrestle with this transition from law to grace. Some Jewish believers insisted that Gentiles who came to faith in Jesus must be circumcised and follow the law of Moses. This issue became so important that the church leaders gathered in Jerusalem to discuss it thoroughly:

Acts 15:10-11: Now then, why do you try to test God by putting on the necks of Gentiles a yoke that neither we nor our ancestors have been able to bear? No! We believe it is through the grace of our Lord Jesus that we are saved, just as they are.

The apostle Paul made this truth central to his teaching. He explained repeatedly that no one is justified by observing the law, but only through faith in Jesus Christ:

Galatians 2:16: Know that a person is not justified by the works of the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by the works of the law, because by the works of the law no one will be justified.

In his letter to the Romans, Paul carefully explained how the law served its purpose of revealing sin and pointing people to their need for a Savior:

Romans 3:20-22: Therefore no one will be declared righteous in God’s sight by the works of the law; rather, through the law we become conscious of our sin. But now apart from the law the righteousness of God has been made known, to which the Law and the Prophets testify. This righteousness is given through faith in Jesus Christ to all who believe.

(Notebook Moment: Have you ever found yourself trying to earn God’s favor through good behavior rather than resting in His grace? How does understanding the purpose of the law help you trust more fully in what Jesus has done for you?)

This doesn’t mean that God’s moral standards have changed or that we can live however we want. Rather, Jesus fulfilled the law by perfectly keeping every commandment and by suffering the penalty that our lawbreaking deserved. Now, through faith in Him, His perfect righteousness is credited to us, and His Spirit enables us to live in a way that pleases God—not to earn salvation, but as a grateful response to the salvation we have freely received.

Israel and the Gentiles

The third way Jesus fulfills the Old Testament is by extending God’s salvation to all nations, not just to Israel. This was actually part of God’s plan from the very beginning, though it took time for people to understand it fully. When God called Abraham, He promised that through Abraham’s offspring all nations on earth would be blessed:

Genesis 22:18: And through your offspring all nations on earth will be blessed, because you have obeyed me.

God chose Israel to be His special people, but not simply for their own benefit. Israel was meant to be a light to the nations, showing the world what it looked like to serve the one true God. Through Israel, God would bring the Messiah into the world, and through the Messiah, salvation would reach every tribe and tongue and nation.

The prophets spoke repeatedly about a time when people from all nations would come to worship the Lord. Isaiah painted a beautiful picture of this future day:

Isaiah 2:2-3: In the last days the mountain of the Lord’s temple will be established as the highest of the mountains; it will be exalted above the hills, and all nations will stream to it. Many peoples will come and say, ‘Come, let us go up to the mountain of the Lord, to the temple of the God of Jacob. He will teach us his ways, so that we may walk in his paths.’

Isaiah 49:6: It is too small a thing for you to be my servant to restore the tribes of Jacob and bring back those of Israel I have kept. I will also make you a light for the Gentiles, that my salvation may reach to the ends of the earth.

However, by the time Jesus came, many Jewish people had lost sight of this global purpose. They saw themselves as God’s exclusive people and looked down on Gentiles as unclean outsiders who had no part in God’s covenant promises. The idea that God might save Gentiles without requiring them to become Jews first was shocking and offensive to many.

The book of Acts shows us how the early church gradually came to understand that the gospel was for everyone. At first, the apostles preached only to Jews. Then Philip preached to the Samaritans, who were part Jewish. Then Peter was sent to the home of Cornelius, a Roman centurion, and watched in amazement as the Holy Spirit fell on these Gentile believers:

Acts 10:44-45: While Peter was still speaking these words, the Holy Spirit came on all who heard the message. The circumcised believers who had come with Peter were astonished that the gift of the Holy Spirit had been poured out even on Gentiles.

(Notebook Moment: The early Jewish believers had to overcome deep-seated prejudices to accept Gentiles as equal members of God’s family. What prejudices or divisions do you see in the church today that need to be overcome by the unifying truth of the gospel?)

Paul became the apostle to the Gentiles, carrying the good news throughout the Roman Empire. In his letter to the Romans, he carefully explained how God’s plan had always included both Jews and Gentiles. He showed that all people—whether Jew or Gentile—are under sin and need God’s grace. And he explained that God has not rejected Israel, but rather is using Israel’s temporary hardening to bring salvation to the Gentiles, which will eventually lead to Israel’s salvation as well:

Romans 11:25-26: I do not want you to be ignorant of this mystery, brothers and sisters, so that you may not be conceited: Israel has experienced a hardening in part until the full number of the Gentiles has come in, and in this way all Israel will be saved.

In his letter to the Ephesians, Paul celebrated the mystery that had now been revealed—that through Christ, Gentiles and Jews are fellow heirs and members of the same body:

Ephesians 2:14-16: For he himself is our peace, who has made the two groups one and has destroyed the barrier, the dividing wall of hostility, by setting aside in his flesh the law with its commands and regulations. His purpose was to create in himself one new humanity out of the two, thus making peace, and in one body to reconcile both of them to God through the cross, by which he put to death their hostility.

The book of Revelation gives us a glimpse of the ultimate fulfillment of God’s promise to Abraham—that through his offspring all nations would be blessed. In John’s vision of heaven, he sees people from every nation, tribe, and language worshiping the Lamb who was slain:

Revelation 7:9-10: After this I looked, and there before me was a great multitude that no one could count, from every nation, tribe, people and language, standing before the throne and before the Lamb. They were wearing white robes and were holding palm branches in their hands. And they cried out in a loud voice: ‘Salvation belongs to our God, who sits on the throne, and to the Lamb.’

Conclusion

The Old Testament and the New Testament are not two separate books with two different messages. They are one unified story of God’s redemptive love for humanity. The Old Testament prepares us for the coming of Christ by showing us our need for a Savior, by giving us promises to hope in, and by providing shadows and types that help us understand the reality that would come in Jesus.

Without the Old Testament, we cannot fully appreciate who Jesus is or what He accomplished. We wouldn’t understand why He had to die, why His death was a sacrifice for sin, or why He is called the Lamb of God. We wouldn’t grasp the significance of His being the Son of David or why His kingdom will last forever. We wouldn’t recognize how His life and ministry fulfilled hundreds of specific prophecies spoken centuries before His birth.

At the same time, without the New Testament, the Old Testament remains incomplete. The promises would be unfulfilled, the shadows would have no substance, and the questions would have no answers. The law would still condemn us without grace to save us. Israel’s story would end in exile and judgment without the hope of restoration through the Messiah.

When we read the Old Testament through the lens of the New Testament, we see Jesus on every page. We see Him in the promise of the seed who would crush the serpent’s head. We see Him in the ram caught in the thicket that was sacrificed in Isaac’s place. We see Him in the blood on the doorposts at Passover. We see Him in the bronze serpent lifted up in the wilderness. We see Him in the prophecies of Isaiah about the suffering servant. We see Him in David’s psalms about the righteous one whose body would not see decay.

The three ways we’ve studied in this lesson show us the beautiful unity of Scripture. First, Jesus is the fulfillment of every promise God made—He is the offspring of Abraham through whom all nations are blessed, the Son of David whose throne endures forever, and the Prophet like Moses who speaks God’s words with ultimate authority.

Second, Jesus brings the grace that the law pointed toward but could not provide—He kept the law perfectly in our place, He suffered the penalty our lawbreaking deserved, and He gives us His Spirit to transform our hearts from within.

Third, Jesus breaks down the wall between Jew and Gentile, creating one new humanity united by faith in Him—He fulfills God’s promise to Abraham that all nations would be blessed, and He makes it possible for people from every tribe and tongue to become children of God.

As we study the Bible, we should always remember that the entire story points to Jesus. The Old Testament prepares the way for Him, and the New Testament proclaims Him. Together, they give us the complete revelation of God’s plan to redeem His creation and restore His relationship with humanity. May we read both testaments with fresh appreciation for how they work together to reveal the glory of our Savior, Jesus Christ, the one who fulfills everything God promised and makes us part of His eternal kingdom.

---

Check Your Understanding

Take this 5-question quiz to check your understanding of this lesson.

Congratulations on completing this lesson! Click on the “Next Lesson” button below when you are ready to continue.

---

Go Deeper

This optional section is designed to guide you deeper into some of the topics of this lesson. (Remember that you can always come back to this at another time.) Make sure to have your notebook in hand to write down your thoughts as you answer these questions.

✅ Apply

We have learned that the Old Testament reveals three aspects of God’s character: His power (through creation), His holiness (through the law), and His love (through His promise of a Redeemer). Think about your life right now. What do you need most?

• Do you need to remember God’s power? Perhaps you are facing problems that seem too big to solve, or circumstances that feel completely out of your control.
• Do you need to understand God’s holiness? Maybe you have been ignoring sin in your life, or you have forgotten how serious it is to disobey God’s commands.
• Do you need to experience God’s love? Are you struggling with guilt, feeling abandoned, or doubting whether God truly cares about you?

Choose one area of your life where you most need God’s help right now. Write a short prayer asking God to help you apply these truths to your specific situation. Be honest about your struggles and ask Him to make His power, holiness, or love real in your life today.

🔍 Explore

This lesson teaches that Christ appears in the Old Testament in “pictures”—people, events, and ceremonies that are previews of what Christ would later accomplish. The New Testament writers help us see these connections. Look up each pair of verses below, read them carefully, and then describe the picture of Christ’s work that is being revealed:

• Exodus 17:6 and 1 Corinthians 10:4
• Numbers 21:8-9 and John 3:14-15
• Exodus 12:21-23 and 1 Corinthians 5:7

🔗 Connect

Make connections to other lessons across the ABC curriculum.