I Will Build My Church

Isaiah 51:1–6 | Psalm 138 | Romans 11:25–36 | Matthew 16:13–20
Thirteenth Sunday after Pentecost / Twelfth Sunday after Trinity / Proper 16

Have you ever looked at your life or at the Church and wondered if things are too far gone? Maybe you've watched a child drift from the faith, faced a diagnosis that changed everything, or simply woken up anxious one too many mornings. Maybe you've looked at the state of the Church in our culture and thought, “I'm not sure we're going to make it.” Into all of that, Jesus says something astonishingly simple.

The Most Important Words in the Sentence

"I will build my church, and the gates of hell shall not prevail against it" (Matthew 16:18). Notice who is speaking. Notice who is doing the building. Jesus does not say, "You will build my Church." He does not say, "If you work hard enough, if you remain clever enough, if your institutions are strong enough, if the culture remains favorable enough, then perhaps my Church will survive." He says, "I will build my church."

That promise is the thread running through the scriptures we're looking at today. God remembers what he has promised. God fulfills what he has begun. God remains faithful when circumstances appear to contradict his promises.

Don't Judge What God Can Do by What You Can Presently See

The prophet Isaiah was speaking to a people who desperately needed to hear this. Israel had known catastrophe. Jerusalem had been devastated. Zion seemed ruined. The promises of God looked terribly small compared with the circumstances surrounding them. And so God says in Isaiah 51:1, "Listen to me, you who pursue righteousness, you who seek the LORD: look to the rock from which you were hewn, and to the quarry from which you were dug." Listen. Look. Pay attention. That language keeps appearing through the passage because Israel's problem is partly a problem of vision. They have become so accustomed to staring at the ruins that they are beginning to interpret God through the ruins. And God says, in effect, "Look somewhere else." Isaiah 51:2 continues, "Look to Abraham your father and to Sarah who bore you; for he was but one when I called him, that I might bless him and multiply him." Abraham was one elderly man. Sarah was a barren woman. Not impressive. Not promising. Not the sort of beginning from which you would predict a nation. But God had spoken. And that was enough. God is reminding Israel: “Do not judge what I can do by the size of what you can presently see.” That may be one of the things some of us need to hear today.

The Wilderness Is Real — But So Is the God Who Makes Gardens

Here's what I want you to notice in Isaiah 51:3: "For the LORD comforts Zion; he comforts all her waste places and makes her wilderness like Eden, her desert like the garden of the LORD." Scripture does not pretend the wilderness is already a garden. The waste places are real. That matters. Christian faith does not require us to call loss gain, sickness health, loneliness companionship, or death life. We do not deny the wilderness. We confess the God who is able to make the wilderness bloom. That is a very different thing. And then Isaiah stretches the horizon even farther. In Isaiah 51:6, God says: "Lift up your eyes to the heavens, and look at the earth beneath; for the heavens vanish like smoke, the earth will wear out like a garment...but my salvation will be forever, and my righteousness will never be dismayed." The things that look permanent will pass away. But the promise of God will remain. Sometimes God's promises look fragile only because we have confused visible things with permanent things.

“In the Midst of Trouble” — Not Around It

The Psalms give us this same truth on a more personal scale. In Psalm 138:3, David writes, "On the day I called, you answered me; my strength of soul you increased." Notice what he does not say. He does not say, "On the day I called, every problem immediately disappeared." God strengthened him. Sometimes the grace of God changes the circumstance, but the grace of God changes us in the circumstance. And then David says in Psalm 138:7, "Though I walk in the midst of trouble, you preserve my life." Not around nor above nor untouched by trouble, but "In the midst of trouble." Some of you know exactly what that means. You are still walking through something you would never have chosen. You are grieving. You are waking up anxious. You are watching your body remind you that you are not twenty-one anymore. And perhaps what you most want from God is escape. Sometimes he gives it, but his promise is really much deeper: "I will preserve you here."

You Are Not Responsible for Providence

Then comes one of the great sentences of the Psalm. Psalm 138:8 says, "The LORD will fulfill his purpose for me; your steadfast love, O LORD, endures forever." There is tremendous freedom in that. You are responsible for obedience. You are responsible for faithfulness. You are responsible for repentance when you sin, forgiveness when you are wronged, generosity with what you have, truthfulness in what you say, courage where Christ calls you. However, you are not responsible for providence. You are not required to control every outcome. For parents, you are called to raise your children faithfully. You are not the Holy Spirit. Those who are grieving, you are not required to know what life will look like five years from now. Today has enough weight of its own. "The LORD will fulfill his purpose."

When Faithful Thinking Reaches Its Limits

In Romans 11, the Apostle Paul is wrestling with the same question on an enormous scale. Many of his fellow Jewish people had not received Jesus as Messiah — and for Paul, this was not abstract theology. He loved his people. Their unbelief caused him deep anguish. And beneath that personal sorrow was a theological problem: God had made promises to Israel. So what do we say when history appears to contradict those promises? Paul's answer is clear: "For the gifts and the calling of God are irrevocable"(Romans 11:29). God has not become faithless. God has not lost control of the story. Then Paul does something remarkable. After eleven chapters of some of the densest theological reasoning in the New Testament, he reaches the edge of what has been revealed — and he stops. And he worships. "Oh, the depth of the riches and wisdom and knowledge of God! How unsearchable are his judgments and how inscrutable his ways!" (Romans 11:33). That is not anti-intellectualism. Christianity does not teach us to stop thinking. It teaches us that faithful thinking eventually discovers its limits. Theology begins in Revelation and ends in doxology. There are seasons when faith says, "I understand." There are other seasons when faith says, "I trust." And sometimes mature faith can say little more than, "Oh, the depth." Then Paul gives us the sentence that gathers everything together: "For from him and through him and to him are all things. To him be glory forever. Amen" (Romans 11:36). History does not originate in chaos. Redemption does not depend upon chance. The future is not finally in human hands.

The Question That Changes Everything

And then we come to Caesarea Philippi, where Jesus asks his disciples what people are saying about him. They give their answers — John the Baptist, Elijah, Jeremiah, one of the prophets. All respectable answers. All completely inadequate. Then Jesus makes the question unavoidable: "But who do you say that I am?" (Matthew 16:15). That is the question at the heart of the Christian faith. Not first: What do you think about the Church? Not: Which religious ideas are meaningful to you? But — who is Jesus? Peter answers, "You are the Christ, the Son of the living God" (Matthew 16:16). Jesus is not merely a teacher or prophet or moral example or one spiritual guide among many. He is the Christ. The Messiah. The Son of the living God. And Jesus responds, "You are Peter, and on this rock I will build my church" (Matthew 16:18). My Church. I will build. The Church belongs to Jesus before she belongs to us. That is both comforting and corrective. It is comforting because the future of Christ's Church does not finally depend upon our strength. It is corrective because we do not have permission to remake Christ's Church into whatever we prefer.

The Gates of Death Will Not Have the Final Word

"The gates of hell shall not prevail against it" (Matthew 16:18). The word there is Hades — the realm of the dead. Death itself will not prevail. That promise becomes even more astonishing when we remember what happens next. The Christ who says this will be arrested, beaten, crucified, and buried. For a brief moment it will look as though the gates of death have swallowed him. And then Easter morning comes. The stone is rolled away. The grave is empty. The gates of Hades cannot hold the Head of the Church — and therefore they cannot finally hold his Body either. The Church's security is not that Christians never fail. We do fail. Churches can become unfaithful. Institutions can drift. But Christ does not fail. And because Christ is risen, his Church cannot finally be extinguished. So yes — we should care deeply. We should contend for the faith. Teach our children. Proclaim the Gospel. Repent of our compromises. Serve our neighbors. Pray for renewal. Love always. But we must not panic. Panic is not faithfulness. We are not frightened custodians desperately trying to keep Christianity alive. Our task is faithfulness. The building belongs to Christ.

Putting It Into Practice

These truths are not just for the Church as a whole — they are for each of us in our ordinary lives. Here are some questions worth sitting with this week:

Look back before you look ahead. When circumstances feel overwhelming, remember Abraham — one elderly man — and the barren Sarah. God does not measure possibility the way we do. Where have you seen him work from what seemed impossibly small?

Release what was never yours to control. Some of us are carrying the future of our children, our health, our finances, someone we love. Ask yourself honestly: What am I carrying as though the future depended entirely upon me? Your call is faithfulness. Providence belongs to God. Carrying one another is important, but we carry them to Him and leave and trust them there.

Let honest faith lead to worship. When you face things you cannot understand, the faithful response is not to pretend you have answers — it is to say with Paul, "Oh, the depth." Are you being drawn toward bitterness and fear, or toward deeper trust and worship?

Answer the question Jesus is still asking. "Who do you say that I am?" It's worth asking: What does the actual ordering of my daily life reveal about my answer?

Move from anxious control to courageous faithfulness. Where is Christ calling you — individually, and together as his Church — to stop white-knuckling outcomes and simply trust the One who said, "I will build my church"?

The deepest truth about the Church — and about every Christian life — is not that we are strong enough to hold everything together. It is that Christ is faithful. He has begun his work. He will not abandon it. And the gates of death will not have the final word.