Built on the Rock

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“Now when Jesus came into the district of Caesarea Philippi, He asked His disciples, “Who do people say that the Son of Man is?” And they said, “Some say John the Baptist, others say Elijah, and others Jeremiah or one of the prophets.” He said to them, “But who do you say that I am?” Simon Peter replied, “You are the Christ, the Son of the living God.” And Jesus answered him, “Blessed are you, Simon Bar-Jonah! For flesh and blood has not revealed this to you, but My Father who is in heaven. And I tell you, you are Peter, and on this rock I will build My church, and the gates of hell shall not prevail against it. I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.” Then He strictly charged the disciples to tell no one that he was the Christ” (Matthew 16:13–20).

Grace to you and peace from God our Father and the Lord Jesus Christ. Amen.

Every civilization leaves behind ruins. Massive stone temples become tourist attractions. Mighty empires become chapters in history books. Families sell homes that once seemed permanent. Churches that were full a century ago stand empty today. Time eventually takes almost everything we think is secure.

The problem is not simply that things change. The problem is that we often place our confidence in things that cannot last. Scripture therefore directs our eyes away from what is passing and toward what endures.

That is why the image of a rock appears so often throughout the Bible. A rock represents strength, permanence, and stability. We build on rock because we expect it to remain when everything around it changes.

In our Old Testament reading, Isaiah says, “Look to the rock from which you were hewn” (Isaiah 51:1). A few verses later, however, he tells us that even the created world will not endure forever: “The heavens vanish like smoke, the earth will wear out like a garment.” Yet God declares, “My salvation will be forever, and My righteousness will never be dismayed” (Isaiah 51:6). Heaven and earth will pass away, but God’s salvation will remain.

The question, then, is this: What can we build upon that will truly last?

In today’s Gospel, Jesus answers that question by asking one of His own. “Who do people say that the Son of Man is?”

The disciples report what they have heard: “Some say John the Baptist, others say Elijah, and others Jeremiah or one of the prophets.”

These answers are impressive. The crowds recognize that Jesus is extraordinary. They place Him among the greatest figures in Israel’s history. Yet every answer is inadequate. It is possible to think very highly of Jesus and still not know who He truly is.

The same inadequate answers are still offered today. Jesus is called a great teacher, a moral example, a champion of the poor, a religious genius, or an inspiring spiritual leader. Yet every answer builds on sand if it stops short of the confession Jesus draws from Peter.

So Jesus makes the question personal: “But who do you say that I am?”

Peter answers, “You are the Christ, the Son of the living God.”

“Christ” is not Jesus’ last name. It is His title and office. It means the Anointed One, the Messiah. Peter is confessing: You are the One whom God promised. You are the One for whom Israel has waited. You are the One sent to save sinners. You are not merely another prophet speaking for God. You are the Son of the living God.

This confession stands near the turning point of Matthew’s Gospel. From here, Jesus moves steadily toward Jerusalem, toward the cross, and toward the empty tomb. Peter has confessed the right Christ, but he does not yet understand what the Christ has come to do.

Before Jesus explains that, however, He explains where Peter’s confession came from. “Blessed are you, Simon Bar-Jonah! For flesh and blood has not revealed this to you, but My Father who is in heaven.” Peter did not reason his way into saving faith. He heard Jesus teach and saw His miracles, but the Father revealed to him who Jesus truly is.

The same is true for us. We do not confess Christ because we are wiser or more perceptive than others. As Luther teaches, “I cannot by my own reason or strength believe in Jesus Christ, my Lord, or come to Him.” Faith is God’s gift. The Father reveals the Son through the work of the Holy Spirit in the Word. God gives the confession, and then Christ makes a promise concerning it: “On this rock I will build My Church.”

Notice first who does the building. Jesus does not say, “On this rock you will build My Church.” He says, “I will build My Church.” The Church belongs to Christ. He gathers her. He preserves her. He builds her.

The Church therefore cannot finally rest upon Peter as a man. Peter will soon show how unreliable human beings are. He will rebuke Jesus for speaking about the cross. He will boast that he will never fall away. Then he will deny three times that he even knows Jesus. If the Church rests upon Peter’s character, she is in terrible trouble. The same is true if she rests upon any pastor, bishop, congregation, institution, or human leader.

Peter is blessed not because of some strength within himself, but because the Father has revealed Christ to him. The Church rests upon the Christ whom Peter confesses and upon the apostolic confession that proclaims Him the Christ, the Son of the living God.” The confession cannot be separated from the One confessed. Christ Himself is the cornerstone. The Church is built on the Rock because she is built on Christ.

But what kind of Christ is He?

Peter does not yet understand the answer. Jesus will go to Jerusalem. He will suffer. He will be rejected. He will be crucified. He will bear the sins of Peter, the Twelve, and the whole world. Then, on the third day, He will rise.

The Rock on which the Church stands is the crucified and risen Christ.

Because Christ is her foundation, the Church will not always look successful. Buildings close. Congregations shrink. Christian institutions fail. Pastors disappoint. Christians fall into sin. Cultures that once appeared friendly to the faith can become hostile to it. Everything visible may suggest that the Church is losing. Yet Christ has made a promise: “The gates of hell shall not prevail against it.”

Why will the Church endure? Not because Christians are strong. Not because pastors never fail. Not because institutions last forever. Not because we have discovered the right strategy. The Church endures because Christ endures. Isaiah records God’s promise: “My salvation will be forever.” Jesus declares, “I will build My Church.” That is why the hymn confidently sings: “Built on the Rock the Church shall stand/ Even when steeples are falling.” The steeple can fall. The building can disappear. The institution can fail. But Christ remains.

This leads us to another question: How does the risen Christ build His Church today? How does He gather sinners, place them upon the Rock, and preserve them in the faith?

The later stanzas of “Built on the Rock” direct us away from the building itself and toward what Christ does within His Church: “Here stands the font before our eyes/Telling how God has received us.”

Christ builds His Church through Holy Baptism. At the font, God does not merely give us a symbol that we belong to Him. He places His name upon sinners. He joins us to Christ’s death and resurrection. He receives us as His children.

The hymn continues: “The altar recalls Christ’s sacrifice/And what His Supper here gives us.”

Christ’s sacrifice was completed once for all upon the cross. Yet the crucified and risen Christ still comes among His people. In His Holy Supper, He gives us the fruits of that sacrifice: His true body and blood, given and shed for us for the forgiveness of sins.

Then the hymn directs us to the Word: “Here sound the Scriptures that proclaim/Christ yesterday, today, the same.”

Christ builds His Church through His Word. The same Gospel that created Peter’s confession continues to create ours. The Father revealed Christ to Peter. The Holy Spirit reveals Christ to us through the prophetic and apostolic Word. Through that Word, the Church continues to confess, “You are the Christ, the Son of the living God.”

The Keys also belong to this enduring work. Jesus tells Peter, “I will give you the keys of the kingdom of heaven.”

Christ places His forgiveness into the mouths of His Church. When sins are forgiven in His name, that forgiveness is not merely a hopeful human word. It is Christ’s own verdict, as certain on earth as it is in heaven.

This is how Christ continues to build His Church. He works through the means to which He has attached His promises: Baptism, His Word, Absolution, and His Supper. These things may not appear impressive to the world, but their power does not depend upon their outward appearance. Their certainty rests upon Christ’s promise. Through these gifts, Christ keeps placing Peter’s confession upon the lips of His people.

Jesus’ question therefore still comes to us: “Who do you say that I am?” He does not ask merely what the culture says about Him. He does not ask only what our parents believed or what our church officially teaches. He addresses us: “Who do you say that I am?”

By God’s grace, we answer with Peter: “You are the Christ, the Son of the living God.” We confess Him before our families and neighbors. We confess Him before friends who do not believe. We confess Him before a culture increasingly uncertain what to make of Him. Together, Sunday after Sunday, we confess Him in the Creed.

Yet our confidence does not finally rest in the strength of our confession. Our confidence rests in the One we confess. Our voices may tremble. Our courage may fail. Our faith may sometimes seem terribly weak. Peter himself proves that. But Christ does not change. He is the Rock.

Look around us. Much of what appears permanent will one day be gone. Isaiah says that even heaven and earth will wear out. One day our homes will belong to someone else. Our names will fade from human memory. Even the church buildings we love will someday disappear. But Christ says, “I will build My Church, and the gates of hell shall not prevail against it.”

Where, then, do frightened sinners find something solid enough to stand upon? Not in ourselves. Not in our goodness. Not even in the strength of our faith. We stand upon Christ. Christ who died and rose. Christ who baptized you and forgives you. Christ who feeds you with His body and blood. Christ who comes to you in His Word. Christ who still places this confession upon the lips of His people: “You are the Christ, the Son of the living God.”

Because the Church is built upon this Rock, she shall stand. She shall stand when steeples are falling. She shall stand when this world passes away. She shall stand even when death itself comes. For God’s salvation is forever, and the gates of hell shall never prevail against the Church that Christ Himself builds. Amen.