Class I: Introduction


Welcome to the first of thirteen classes on our life together as a church. In this introductory class, my hope is to give you some idea of why we as Christians need a class like this in the first place. To put it simply, we need this class because two things are true:

First, God calls Christians to gather together in local churches to worship him and to reflect his glorious character to the world.

Second, we are still sinners.

The million dollar question is, how do these two statements work together? God calls us to glorify him by living together in local churches? How can a still sinful people reflect God?

Unity is Hard

One day, all of God’s people will bow before him, perfectly righteous because of Christ and perfectly unified in humble worship and praise. But God still calls us today—the very imperfect people who compose his Church—to the task of displaying the glory of his perfect character.

The question of how that can happen in the church is the focus of this class. In particular, our goal is to understand the opportunities and responsibilities we all have as church members. How can we, as sinful and selfish people, gather together, not with the forced unity that denies differences, overlooks difficulty, or compromises the message of the gospel, but with unity that preserves the message of the gospel and acts as a compelling testimony to its value? How can we respond to sin in our midst without descending to gossip and slander? How can we trust our leaders but still recognize that they are sinners, too? How can we love people who make us feel uncomfortable because they are so different from us? How can we honestly critique an imperfect church without grumbling?

If you’ve been part of a church for any amount of time, you know that these goals are difficult to achieve. Churches far too often become places of division, complaints, and unhappy people. Therefore they fail to display to the watching world the power of the gospel that should be at work within them.

Our goal for this class is to explore a practical blueprint of what makes a church healthy. What makes it a community where sound doctrine expresses itself in love that glorifies God? My prayer is that you will leave this class with a better understanding of what the Bible says about being a healthy church, and also with some clear ideas of what you can do to help build a healthy church.


Let’s begin by considering a foundational question: Why is the church important? More specifically, why is it important to God?

To answer that question, let’s look at Ephesians 3 and 4, where Paul lays out the importance of the church in God’s plan of redemption. I’ll run through the whole passage, and then summarize some critical takeaway points.

Unlocking the Mystery of the Gospel

To give you some context, Paul has spent chapters 1 and 2 describing the power of the gospel—that though we as Christians were dead in our transgressions, we are now alive in Christ and reconciled both to God and to each other. Let’s pick up his train of thought in Ephesians 3:2:

Surely you have heard about the administration of God’s grace that was given to me for you, that is, the mystery made known to me by revelation, as I have already written briefly. In reading this, then, you will be able to understand my insight into the mystery of Christ. (vv. 2-4)

What is this mystery that Paul understands so well? Skip ahead to verse six:

This mystery is that through the gospel the Gentiles are heirs together with Israel, members together of one body, and sharers together in the promise in Christ Jesus.

You see? Paul is excited about the fact that Christianity has united Jews and Gentiles together into one body. The hatred and enmity which had existed between them for centuries is overcome in the gospel. As Paul put it a little earlier in 2:14, Christ has “broken down in his flesh the dividing wall of hostility” between Jews and Gentiles.

Back to chapter 3. In verse 8, Paul says that the proclamation of this mystery—this gospel-induced peace between Jew and Gentile—is central to his ministry:

Although I am less than the least of all God’s people, this grace was given me: to preach to the Gentiles the unsearchable riches of Christ, and to make plain to everyone the administration of this mystery, which for ages past was kept hidden in God, who created all things.

The Purpose of Gospel Unity

But why is unity in the gospel so important? In verse 10, Paul gives us a unique glimpse into God’s purpose:

His intent was that now, through the church, the manifold wisdom of God should be made known to the rulers and authorities in the heavenly realms.

Who are the “rules and authorities” that Paul mentions here? We don’t really know. The phrase “in the heavenly realms” suggests that it refers to the spiritual dimension that exists beyond the physical.

What is absolutely clear, though, is that it is through the church—and specifically, through the unity of Jews and Gentiles within the church—that God is bringing glory to himself by showing off to everyone (verse 9) his manifold wisdom.

How does the church display the manifold wisdom of God? Only an all-wise God could devise a way to reconcile his love and his justice while saving a rebellious people who are estranged from him and from one another.

Unity Applied—How Then Should We Live?

Through the rest of chapter 3, Paul prays for the family of God. He asks God to strengthen them through his Holy Spirit. He also prays that, as Christ dwells in their hearts through faith, they would come to understand just how all-encompassing Christ’s love is for them, and thus be “filled with all the fullness of God” (see verses 14-21).

In chapter 4 Paul begins to apply the truths we have just discussed, calling the Ephesian Christians to “live a life worthy of the calling you have received.” My guess is that when you hear this exhortation, you probably start to think immediately of your own personal holiness. But if you keep that exhortation firmly planted in the context of chapter three, it’s clear that he doesn’t have our individual holiness in mind here so much as our life together as a church!

Look at verses 2-3, where Paul talks about what should characterize our relationships in the church:

Be completely humble and gentle; be patient, bearing with one another in love. Make every effort to keep the unity of the Spirit through the bond of peace.

Paul has more than one person in mind here. He’s talking to a group of people, not just individuals.

Through the next few verses, Paul describes our calling as one body and explains that our unity with each other is fostered by the gifts God has given to his people (verses 4-11). And what’s the goal of these gifts? Verses 12-13:

To prepare God’s people for works of service, so that the body of Christ may be built up until we all reach unity in the faith and in the knowledge of the Son of God and become mature, attaining to the whole measure of the fullness of Christ.

Some Things to Remember

Well, that’s a lightning run through two marvelous chapters of Scripture. Let’s pause for a moment and notice three truths in this passage that are of critical importance:

First, the unity of the church is central to the message of the gospel. One of the great accomplishments of Christ’s work is that he has broken down the dividing walls of hostility that exist—because of sin—between human beings. Through the blood of Christ we are reconciled with God and we are reconciled with one another. It cannot be otherwise.

Second, church unity showcases the wisdom of God. The church isn’t a collection of people who merely tolerate one other long enough to sing some songs and hear a sermon every Sunday; the church is a gathering of people who demonstrates a unity so powerful that it can only have come to pass by the hand of God.

Third, cultivating unity is our responsibility as church members. It is the entire church that has been gifted by the Spirit, and so Paul calls the entire church to keep the unity of the Spirit through the bond of peace. And, as we see in 1 Corinthians 1 and James 2, the New Testament authors will rebuke the entire church when unity is damaged. Not just church leaders. Church members.

Unity Throughout the Bible

So what is God’s goal for the church? Unity. Why? Because when redeemed sinners with little in common choose to love each other, that displays God’s wisdom and glory like nothing else.

This truth is not unique to the book of Ephesians. It is found throughout the Bible. Consider Jesus’ words in John 13:34-35:

A new command I give you: Love one another. As I have loved you, so you must love one another. By this all men will know that you are my disciples, if you love one another.

Jesus continues this thought in his prayer for believers in John 17:

May they be brought to complete unity to let the world know that you have sent me and have loved them even as you have loved me. (v. 23)

Or think of Luke’s description of the early church in Acts 4:

All the believers were one in heart and mind . . . with great power the apostles continued to testify to the resurrection of the Lord Jesus, and much grace was upon them. (vv. 32-33)

Even in the Old Testament, the mission of God’s people was to reveal—as a corporate body—God’s character to the nations around them. When God chose Abraham, his ultimate goal was not to save just Abraham as an individual. God intended to make of Abraham “a great nation” that would bless all the families of the earth (Gen. 12:1-3).

Similarly in Ezekiel 36, God promises to save and reestablish the nation of Israel so that all the nations around them would know that he is God. It was his goodness to the people as a whole that would glorify him in the world.

Unity is Not Just an Option

We can see from all this that unity among God’s people is not just an optional addition to our lives as Christians. It is an integral part of our life as God’s people. Remember how starkly John puts this in 1 John 4:20:

If anyone says, ‘I love God,’ yet hates his brother, he is a liar. For anyone who does not love his brother whom he has seen, cannot love God, whom he has not seen.

The bottom line is that we need to realize that focusing on “my individual life as a Christian” is fundamentally wrong-headed. God accomplishes his purposes in believers primarily corporately, not individually. That’s why the word-pictures the Bible uses to describe the church—living stones built into a spiritual house, members of a body, and so forth—emphasize the communal nature of the church. God will fulfill his purpose for the church as it acts in unity, as a community of believers.


Ironically, the concept of unity has become quite divisive over the past hundred years or so. People have understood the Bible’s call for Christian unity in many different and conflicting ways. So what do we mean, exactly, when we talk about Christian unity?

One Extreme—Unity at All Cost

Some people say that Christian unity means that all people who call themselves Christians should organize together institutionally, or at least cooperate together as a single body of believers. The problem with Christianity, they say, is that our doctrinal disagreements—between Catholics and Protestants, or Evangelicals and theological Liberals—damage our ability to influence this world for the kingdom of God. Therefore, we should set those differences aside and unite in the greater cause of making the world better.

The problem with this expansive view of unity, as many Christians have noted, is that it would be a shallow unity, indeed. Many who call themselves “Christians” would disagree on some very fundamental questions:

  • What does it mean to be a Christian?
  • Who is God?
  • Who is Jesus Christ?
  • What must people do to be saved?
  • Do we even need to be saved from sin at all?

When there is disagreement about basic issues like those, it’s hard to imagine how any real unity can be fostered. Sure, you could ignore such questions and declare yourselves unified anyway. But organizational unity for its own sake is pretty meaningless, isn’t it? Even worse, it can confuse the world as to the nature of Christianity and the gospel.

It is certainly a good thing to cooperate with others for the sake of a common goal—working with Roman Catholics to protect the rights of the unborn, for example. But while that is a type of unity, it’s not Christian, per se. I’ll partner with non-Christians to protect the rights of the unborn.

The Other Extreme—No Unity At All

At the other extreme are those Christians for whom unity is almost a bad word. Such separatists may be right to regard the kind of ecumenism that we just considered as confusing and contrary to gospel purposes. But these separatists can go too far, declaring that they will share Christian fellowship only with those who agree with them on every point of doctrine.

Many separatistic churches place undue focus on doctrines that are not clear in Scripture, such as their own understanding of the end times or particular rules for Christian living. As a result, they become known more for being divisive, schismatic, and legalistic than for holding out the life of the gospel.

The idea that a local church would isolate itself from other churches is almost as preposterous and unbiblical as an individual Christian isolating himself from other Christians. Even as we struggle against a wrong-headed, utopian view of globally organized Christian unity, we must also fight to reclaim the high place that real Christian unity should hold in our lives—both between individual Christians and churches.

Avoiding the Extremes—True Christian Unity

In this fallen world, real Christian unity falls in between those two ends of the spectrum I just described. Perhaps a helpful way to get our heads around the kind of unity Paul talks about in Ephesians is to think of it in terms of an action, a purpose, a source, and a place.

1. The action that defines Christian unity is love. In particular, it is love for our brothers and sisters in Christ that crosses worldly boundaries. In this world, people divide along all kinds of socio-economic, racial, and ethnic lines. And people certainly divide when one person sins against another. But as we have seen, the gospel of Jesus Christ tears down those walls, both the walls of life circumstance and the walls of offence-rendered and hurt-received. Now we as Christians are called to love those whom we would not naturally be drawn to love. Think of Jesus’ words in Matthew 5:46.

If you love those who love you, what reward do you have? Do not even the tax collectors do the same?

Or chapter 18:21-22

Then Peter came to Jesus and asked, "Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?" Jesus answered, "I tell you, not seven times, but seventy-seven times.

2. The purpose of Christian unity is the glory of God in the vindication of his gospel. Unity that exists for any other purpose may well be valuable, but it is not the Christian unity that we are exploring in this class.

This is a crucial point in determining whether we may unite with another group of people and describe it as Christian unity. Is this other church or organization laboring for the same God as we are? Are they seeking to proclaim and vindicate the same gospel? Or are there fundamental differences that will cause people to believe in a different gospel altogether?

These are not always easy questions to answer, but that does not mean we are free not to ask them. The decision to unite with another church in gospel work is one that has enormous implications. The last thing we want to communicate to the world is that we as a church are somehow “okay” with beliefs that actually repudiate the biblical gospel.

3. The source of Christian unity is the love of Christ. As John puts it, “We love because he first loved us” (1 John 4:19). Real Christian unity has at its root a deep understanding that we are forgiven in Christ.

Do you remember Jesus’ words in Luke 7:47? “He who is forgiven little, loves little.” And he who has been forgiven much, loves much. Unity that glorifies God and vindicates the wisdom of the gospel is unity that is powered by our understanding that we have been forgiven in Christ. When Christ’s love for us is the source of our love for one another, that is a supernatural love, one that can only be explained by the power of God working in us. But if unity is driven by an affinity which is familiar to the world—one based merely on a desire to clean up a neighborhood, for example, or effect some sort of social change—how will the wisdom of God to the “rulers and authorities in the heavenly realms” be displayed? No, the unity for which we strive is one based on something that the world simply cannot fit neatly into its godless categories. It’s a transcendent unity based on Christ’s love for us.

4. Finally, the place where Christian unity is primarily worked out is the local church. Of course, Christian unity is not limited to an individual local church, but it works itself out most practically in that context. It is in the local church that we learn to rejoice with people with whom we may not naturally rejoice, and to weep with people with whom we may not naturally weep. In the local church we learn to share our lives with people who share one profound love with us: the love of our Lord Jesus Christ who has forgiven us of our sin.

Understanding all that, we might define Christian unity like this:

True Christian unity is found in God-glorifying, gospel-revealing love for all brothers and sisters in Christ, fueled by our forgiveness in Christ that expresses itself most clearly in the assembly of the local church.

That is the kind of Christian unity that will declare God’s wisdom to the world.


The unity we seek in the local church is not just theoretical. It has real implications for our lives, and real benefits to us as Christians. For the next few minutes, I want us to turn our attention to exploring some of the benefits that unity brings to a local congregation.

As we walk through each of these, keep two questions in mind:

  • First, do you see this particular benefit in our church generally?
  • And second, are your own relationships with the members of this church structured in such a way that this benefit accrues to you and to others?

Here then are some of the benefits of Christian unity that Scripture holds out to us:

Assurance of Salvation
In 1 John 3, we read:

We know that we have passed from death to life, because we love our brothers. (verse 14)

And later,

Dear children, let us not love with words or tongue but with actions and in truth. This then is how we know that we belong to the truth, and how we set our hearts at rest in his presence whenever our hearts condemn us. (vv. 19-20)

John is writing here about the importance of loving our brothers and sisters in Christ. When we look at our relationships with other Christians and see unity and love rather than discord and strife, it should encourage us that we are in fact the children of God. Unity in the body of Christ is an important part of a believer’s assurance of salvation.

The author of Hebrews writes in Hebrews 10:23-25:

Let us hold unswervingly to the hope we profess, for he who promised is faithful. And let us consider how we may spur one another on toward love and good deeds. Let us not give up meeting together, as some are in the habit of doing, but let us encourage one another—and all the more as you see the Day approaching.

These verses begin with a stirring call—to hold unswervingly to the hope we profess. That’s really hard to do, which is exactly why God has written these words not to you as an individual, but to us as a church. Our life together as a church is important because God knows we’re not self-motivated all the time. We need each other’s prayer, correction, and encouragement so that we may love each other. This type of encouragement cannot happen in an atmosphere of dissention and strife. It happens when there is unity.

The third benefit of unity I’d like us to consider comes again from Ephesians 4. Unity protects our doctrine. Look at where we left off in verse 14. Remember, Paul was writing about building up the unity of the church.

Then we will no longer be infants, tossed back and forth by the waves, and blown here and there by every wind of teaching and by the cunning and craftiness of men in their deceitful scheming. Instead, speaking the truth in love, we will in all things grow up into him who is the Head, that is, Christ. From him the whole body, joined and held together by every supporting ligament, grows and builds itself up in love, as each part does its work. (vv. 14-16)

What will have this kind of impact? The unity Paul has been describing for the previous thirteen verses. Unity protects our doctrine. It protects us from the tyranny of faddish teaching, from the danger of being pulled into error. More than creeds and statements of faith, more than bishops and popes, unified congregations have been the primary means God has used to protect the core teachings of the Christian faith.

Today, efforts to recapture unity often get a bad reputation precisely because they come at the expense of orthodoxy. But far from seeing a delicate balancing act between doctrine and unity, Paul sees unity as our main hope for preserving our doctrine.

In John 17, Jesus prays,

My prayer is not for them alone. I pray also for those who will believe in me through their message, that all of them may be one, Father, just as you are in me and I am in you. May they also be in us so that the world may believe that you have sent me. . . . May they be brought to complete unity to let the world know that you sent me and have loved them even as you have loved me. (vv. 20-21; 23b)

The church’s unity is one way that non-Christians will recognize the divinity of Christ and his divine mission. Moreover, it is part of how they will come to understand the love of God.

That ambitious, God-given objective should make us consider the role our church plays in our own evangelism. Of course evangelism is more than simply bringing people to church, but that doesn’t mean that the church has no role to play in evangelism. Exposing a non-Christian to the love we have for each other as Christians is a powerful witness to the work of God in our lives.

There are other benefits of unity we could consider as well:

  • A unified church is more likely to pray for itself and others.
  • Its members are far better able to hold each other accountable, because they know each other and love each other.
  • Even the disciplinary actions of a unified church are more powerful because they are more obviously driven by love and not factionalism.
  • A unified church has the luxury of focusing the attention of its leadership outward rather than on solving problems within. The list goes on and on.


Remember the question with which we began the class: how can an imperfect people display the glorious character of a perfect God? What’s the answer?

A still sinful people can display both the love and holiness of God as they live in gospel unity: a unity that doesn’t come from white washing sin, but calls it what it is—sin; but a unity that’s born of the forgiveness of sin—the forgiveness of Christ which we both proclaim and extend to one another.

This entire course is a class about unity—unity that proclaims Jesus Christ’s greatness to the people around us because it flows from and celebrates God’s work of redemption.

Over the next twelve weeks, we think practically about how we can build a church marked by that kind of unity, one that therefore protects and proclaims the life-changing message of the gospel. I pray that God will use these weeks to help us better understand the role that each of us is to play in that great work.

Jamie Dunlop

Jamie Dunlop is an associate pastor of Capitol Hill Baptist Church in Washington, D. C. He is the author of Budgeting for a Healthy Church: Aligning Finances with Biblical Priorities for Ministry.

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