If Your Brother Sins | Matthew 18:15-20

Intro

Imagine two next-door neighbors living in nearly identical spec homes. (I owe credit to Doug Wilson for this analogy.) Both families have the same number of kids, who are basically the same ages. They live in mirror-image spec homes. The husbands even work for the same company. One difference: the Joneses drive a Honda Odyssey, the Smiths a Toyota Sienna.

But there’s one major difference: the Smiths’ house is neat and tidy, while the Jones’s house is a disaster. The sink is overfilled with dishes from last month. You can’t see the flooring in any of the bedrooms because of the clothes and toys. The surface of every table and counter is buried in junk mail and bills. and last year's Christmas cards. 

So what’s the difference between the Joneses and the Smiths? They both track in the same amount of dirt, use the same number of dishes, get the same amount of mail, and wear the same amount of clothes in a week. The difference is that the Smiths clean up the mess they make; the Joneses don’t.

This may come as a shock or a disappointment, but the difference between the Church and the world is not that people in the world sin and Christians in the Church don’t. The difference is that we know Jesus Christ, our Savior who died for our sins. Therefore, Christians should know how to clean up when sin makes a mess.

Do you know what to do when another Christian sins against you?

Matthew 18:15–20

15 If your brother sins against you, go and tell him his fault, between you and him alone. If he listens to you, you have gained your brother. 16 But if he does not listen, take one or two others along with you, that every charge may be established by the evidence of two or three witnesses. 17 If he refuses to listen to them, tell it to the church. And if he refuses to listen even to the church, let him be to you as a Gentile and a tax collector. 18 Truly, I say to you, whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven. 19 Again I say to you, if two of you agree on earth about anything they ask, it will be done for them by my Father in heaven. 20 For where two or three are gathered in my name, there am I among them.

A Redemptive Process

In Matthew 18, Jesus prescribes his redemptive process for handling sin in the Church: “If your brother sins against you” (v. 15). Christians sin against each other. This is a reality you must be prepared for.

One of the defining characteristics of any family is the way it handles sin and conflict. Is sin ignored? Is it celebrated? Is it piled up in heaps or swept under the rug? Or is sin dealt with God’s way?

We’ve spent January exploring corporate habits of grace in the life of the church. And make no mistake, the process by which a family—or church—handles sin quickly becomes a deeply ingrained habit. You could probably write out a script for how conflict goes in your household: first, he says or does something (or forgets to say or do something); then, she reacts like this or that; next, he will say thus and such.

The issue is always changing, because the issue is never the issue. Last week, it was the budget. Today it’s the paint color. The real issue is the process, and until the process changes, nothing will change.

Church discipline is the redemptive process Jesus gave his Church for handling sin. As the biblical practice for dealing with sin as a church family, it is to be our habit. And it is a habit of grace because God graciously asserts himself through this process to restore wayward sheep, preserve our unity, and glorify the name of Christ.

So how does the Lord Jesus teach his Church to handle sin and conflict? I want to paint with broad strokes to show you the principles that inform what discipline is, how it works, and why it works. 

What Is Church Discipline?

The word discipline has all kinds of connotations. And context matters. If you walked into a locker room and you saw the word discipline emblazoned on the wall, along with team values like teamwork, excellence, and effort, you would take it to be a positive thing. But for many people, putting the words church and discipline together evokes suspicion and fear. Doesn’t it sound so legalistic? Judgmental? Authoritarian?

In Scripture, the words for discipline mean instruction, training, and education. In the Old Testament, the Hebrew word musar means instruction or discipline. It appears thirty times in the book of Proverbs alone, often showing up in parallel with the word for reproof or rebuke. So instruction and correction are closely related. It is, as Jay Adams calls it, “education with teeth.”

We don’t have time to read all those passages, but it is a profitable word study. Here’s a summary: discipline and reproof can be either despised, resented, hated, rejected, and ignored, or heeded, loved, and listened to. 

The one who rejects discipline and reproof leads others astray; is stupid and foolish; reaps poverty and disgrace; despises himself; and dies early.

But the one who receives discipline and reproof walks the path to life; loves knowledge; is honored; is prudent; and gains intelligence.

In Greek, the word is paideia: to instruct, educate, or enculturate. Christian fathers are commanded to raise their children in “the discipline and instruction of the Lord” (Ephesians 6:4). Second Timothy 3:16 says, “All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness.” In Titus 2:11–12, it’s the very grace of God that does the disciplining or training: “For the grace of God has appeared, bringing salvation for all people, training us to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age” (Titus 2:11–12). The words discipline and discipleship are obviously related: discipline is instruction and a disciple is a learner.

Foundational to the entire concept of discipline is this truth from Proverbs 3:11–12: “My son, do not despise the LORD’s discipline or be weary of his reproof, for the LORD reproves him whom he loves, as a father the son in whom he delights.”

The author of Hebrews cites that verse and adds this astonishing promise: “For the moment all discipline seems painful rather than pleasant, but later it yields the peaceful fruit of righteousness to those who have been trained by it” (Hebrews 12:11).

And in his address to the Church in Laodicea in Revelation 3, the Lord Jesus says, “Those whom I love, I reprove and discipline, so be zealous and repent” (Revelation 3:19).

So church discipline is a family thing. As a father, I discipline my children because I love them. I don’t have any right to discipline my neighbors’ children. Church discipline is applied to disciples of Jesus, those who have professed faith in Christ, been baptized in his name, and joined to his Church. The world outside of the Church is full of sinners who need to hear the Gospel. But the Church itself is full of disciples battling remaining sin.

So discipline refers to a wide range of activities—some informal, private and personal, some formal, public, and corporate—by which the Church trains, instructs, and corrects Christians. 

Proactive church discipline is like routine, preventative maintenance on your car: you change the oil every 3,000 miles, keep your tires properly inflated, change your windshield wipers, and check your battery. This would include meeting together in Discipleship Huddles to confess our sins and point one another to Christ.

Reactive or corrective church discipline is like an emergency repair: your transmission goes out, your fuel injector needs to be replaced, your flux capacitor breaks. This is necessary when sin has caused a break in fellowship between believers (like Jesus mentions here), or when a believer is caught in unrepentant sin.

Church discipline is the redemptive process Jesus gave to his Church for correcting sin in the Church.

And church discipline has several aims. The most immediate and obvious aim is to rescue the wayward sinner. Matthew 18:15: “Go and tell him his fault …. If he listens to you, you have gained your brother.” That is the goal, and we see it everywhere in Scripture. James writes, “My brothers, if anyone among you wanders from the truth and someone brings him back, let him know that whoever brings back a sinner from his wandering will save his soul from death and will cover a multitude of sins” (James 5:19–20; cf. Gal 6:1).

A second aim is to restore fellowship between believers. To gain your brother refers not only to rescuing his soul, but to repairing the broken relationship. Relational sin puts you out of fellowship; reconciliation restores fellowship. In Matthew 5:24, Jesus commands those who are out of fellowship to “be reconciled.” To be reconciled means animosity, bitterness, and hostility are replaced by friendship and fellowship.

A third aim of church discipline is the health of the church. Proverbs 10:17 says, “Whoever heeds instruction is on the path to life, but he who rejects reproof leads others astray.” Not only does a wayward Christian endanger himself, but he leads others astray. The church in Corinth was sick and infected when it left scandalous sin unaddressed. Paul wrote, “Do you not know that a little leaven leavens the whole lump? Cleanse out the old leaven that you may be a new lump” (1 Corinthians 5:6–7). Church discipline upholds God’s Word and God’s ways, which serves as a gracious warning to the entire Church to forsake sin and cling to Christ.

But the ultimate goal of church discipline is the glory and honor of God’s name. Taking God’s name in vain means more than saying OMG or GD. Taking God’s name in vain means bearing his name in a way that is false, deceptive, empty, or meaningless.  As a baptized believer, you bear the name of Christ. Therefore, the sin of Christians mischaracterizes and misrepresents God. When those who bear the name of Christ live in open, unrepentant sin, the name of Christ is dishonored and defamed. Therefore, the aim of church discipline is to maintain the glory due to Christ.

How Does Church Discipline Work?

In Matthew 18, Jesus outlines four incremental steps for handling sin between Christians. We’ll spend the bulk of our time on Step 1, because that’s where everything starts and where, by God’s grace, most things should end. It’s also the step that everyday church members must know how to initiate. I pray this will be our corporate habit, our family process, the way we do things.

But because the detailed mechanics are important, I want you to know where to find them. The entire process is outlined in our church bylaws (available on the Members page of our website) and the Sovereign Grace Book of Church Order, available online.

As we often say, we love our church polity like we love a home security system—not because the policies and procedures are precious to us, but because they protect the people who are precious to us.

Step 1: One on One

“If your brother sins against you, go and tell him his fault, between you and him alone. If he listens to you, you have gained your brother” (Matthew 18:15).

The first thing to note is that this is a command, not a suggestion. Jesus commands you to take the initiative whenever you think you have been wronged.

Multiple sermons could be preached on this, but here’s the point: deal with people directly. Almost every conflict and division in the church would be extinguished if Christians obeyed Jesus and practiced this step. “For lack of wood the fire goes out, and where there is no whisperer, quarreling ceases” (Proverbs 26:20). Fire can’t burn without fuel; quarrels and conflicts can’t spread without gossip.

What happens when you take your grievance against Pete to Tom, Dick, and Harry? Now Tom, Dick, and Harry have a grievance against Pete, but Pete has no idea why.

“A whisperer separates close friends” (Proverbs 16:28).

Here’s a wise rule of thumb. Before you open your mouth to anyone else about someone else’s sin, ask yourself, “Have I communicated this concern directly to that person yet?” If not, bite your tongue.

Of course, there’s another side to the gossip equation. Proverbs 20:19 says, “Whoever goes about slandering reveals secrets; therefore do not associate with a simple babbler.” So imagine someone approaches you with “concerns” about Jane. You want to be a good friend, to listen and care for your friend who is obviously hurt, bothered, or discouraged by whatever Jane did to her. But the loving thing to do is to (gently) interrupt and ask: “Before you go on, have you communicated these exact things to Jane yet? If not, I shouldn’t hear about it.”

Don’t be surprised if this is hard to do! “The words of a whisperer are like delicious morsels; they go down into the inner parts of the body” (Proverbs 18:8, repeated in 26:22). There’s something about gossip that is juicy and delicious and satisfying. And we have all kinds of ways to dress it up Christianly.  You can call it “seeking counsel” or “processing” or “venting” or “sharing a prayer request,” but it’s gossip if you have not yet obeyed Step One from Jesus: “Go and tell him his fault, between you and him alone.”

Why, you might ask, do you have to be the one to act if you’re not the one at fault? Because only you know when you have been offended. The person who offended you may have no idea, in which case, you’ll wait forever for a confession. When you obey Jesus’ command to go to that person, you take responsibility for your reactions, and you graciously give the other person the chance to confess or explain.

Of course, it’s totally possible you were not actually sinned against. Having hurt feelings is not the same thing as being sinned against. Sin is that which violates God’s Law, not that which offends someone. But if you harbor offense without saying anything, you have broken fellowship.

I heard a story once of a church member who wanted to talk to the pastor about a serious personal concern. She tried to approach him one Sunday, but he ignored her and rushed by her. She was deeply hurt and offended. As it turned out, he was sick that day and was rushing to the bathroom. This does not mean that every relational bump must result in confrontational conversations.

It is often wise to overlook an offense. “Good sense makes one slow to anger, and it is his glory to overlook an offense” (Proverbs 19:11). “Above all, keep loving one another earnestly, since love covers a multitude of sins” (1 Peter 4:8; cf. Prov 10:12).

Jay Adams offers this wise insight: “Any offense that doesn’t get between us and the one who committed it—does not need to be raised. But anything that creates an unreconciled state between us and another must be brought up and dealt with. That is to say, any matter which is carried over to another day, any matter which makes you feel different toward that person for more than a passing moment … must be brought up.”

Be careful here! Because we all prefer to avoid awkward conversations, you will want to tell yourself it’s not a big deal and it doesn’t bother you. But if the relationship is cold, if you feel awkward and uncomfortable around that person, if you struggle to force a smile or keep up a conversation, if you take the long way around when you see them coming, you’re lying to yourself and not overlooking the offense.

If you can’t let it go and it’s affecting your ability to relate to that person, Jesus says it’s on you to take the first step. Go, deal directly and personally. Trust Jesus and lean into the awkwardness and tension in obedience to Jesus.

Now, there are times when overlooking sin is not an option. Sin that is “outward, serious, and unrepentant” (Leeman) cannot be ignored. This would include scandalous sins like sexual immorality or drunkenness (1 Cor 5:11). Say you become aware that another member in the church is having an affair, or got wasted at Wiley’s on Friday night, or blew through his last paycheck at Grand Falls, or is engaged in some dishonest business deals, or uses foul language and raunchy jokes at work. These are not “overlookable” offenses because they are public, not personal.

Other sins that cannot be overlooked include promoting false doctrine (1 Tim 1:3–4) and stirring up division (Titus 3:10). If you care about your brother’s soul, the health of the church, and the glory of Jesus, you have to say something.

Of course, we have all kinds of reasons for not going directly to the person who offended us. I don’t want to make things worse! I’m not really a confrontational person. I’m pretty sure he wouldn’t take it very well. Jesus takes away all our excuses in step two.

Step 2: One or Two Others

“But if he does not listen, take one or two others along with you, that every charge may be established by the evidence of two or three witnesses” (Matthew 18:16). The single factor that moves the process from one step to the next, all the way through, is whether or not the brother in sin listens, which implies repentance: “If he does not listen” (v. 16); “If he refuses to listen to them …” (v. 17); “And if he refuses to listen even to the church …” (v. 17).

Notice how the circle of people involved gradually gets larger as the process unfolds. From one-on-one (v. 15) to one or two others (v. 16) to the church (v. 17). Again, the principle is only those who need to know should know. However, it also means that you must never promise absolute confidentiality. There are times when Jesus requires you to involve others in the redemptive process.

Now, Jesus’ point here is not that ganging up on the brother is necessarily more effective. The core issue is biblical justice—something our culture knows little about. Jesus is referring to Deuteronomy 19:15: “A single witness shall not suffice against a person for any crime or for any wrong in connection with any offense that he has committed. Only on the evidence of two witnesses or of three witnesses shall a charge be established.” 

It’s a serious thing to charge another believer with sin. The truth of that charge must be established by others. Misunderstandings and false accusations are real. So involving others at this stage leaves open the possibility of innocence. 

In other words, the “one or two others” are not to go into things with their minds made up, taking the side of the one who recruited them. Proverbs 18:17 says, “The one who states his case first seems right, until the other comes and examines him.” The witnesses are not on either side; they are on the side of truth and reconciliation. They are there to mediate, to hear the facts from both sides, to determine if there is a legitimate charge, and if there is, to appeal to the sinner to repent. 

Step 3: The Church

“If he refuses to listen to them, tell it to the church” (v. 17a). At this point, the process moves from informal to formal, as it involves the church as an institution. In our context, the first step would be to inform the elders, who are representatives of the whole church (cf. Ex 3:15–16). The elders would then determine when and how to communicate with the whole church (membership), either by written letter or in a members-only family meeting.

At this stage, the brother in sin is still regarded as a brother, but this is where the whole church participates in the process of discipline. Jay Adams helps again: “The reason why the congregation is told is so that as a whole they may have an opportunity to help the offending, willful brother or sister come to repentance.”

We see this applied in 2 Thessalonians 3:14–15: “If anyone does not obey what we say in this letter, take note of that person, and have nothing to do with him, that he may be ashamed. Do not regard him as an enemy, but warn him as a brother” (cf. 1 Cor 5:11).

At this stage, the person is still regarded as a brother or sister in Christ, but the members of the church are to avoid casual interactions that would indicate nothing is wrong. The brother in sin, having been warned, would also be restricted from eating the Lord’s Supper with the church. These are not yet punitive, vindictive measures; they aim at repentance and restoration.

Step 4: Removal

“And if he refuses to listen even to the church, let him be to you as a Gentile and a tax collector” (v. 17b). What does that mean, to treat someone “as a Gentile and a tax collector”? Keep in mind, Jesus’ audience in Matthew 18 was Jewish. When he speaks of a Gentile, he’s referring to a stranger to God’s covenant people. A tax collector was a Jew who had sided with the enemies of God’s people.

This is the most heartbreaking step, as the unrepentant person is removed from the church. But what does that mean? It doesn’t mean that person is banned from attending church. Unbelievers are welcome here—except those who would seek to disrupt or distract. But it does mean that the church formally communicates that we no longer believe that person’s profession of faith. His stubborn, willful refusal to turn from sin gives us no reason to believe that he is a Christian.

The example of this stage of church discipline in Paul’s letter to Corinth is worth observing:

“It is actually reported that there is sexual immorality among you, and of a kind that is not tolerated even among pagans, for a man has his father’s wife. And you are arrogant! Ought you not rather to mourn? Let him who has done this be removed from among you. For though absent in body, I am present in spirit; and as if present, I have already pronounced judgment on the one who did such a thing. When you are assembled in the name of the Lord Jesus and my spirit is present, with the power of our Lord Jesus, you are to deliver this man to Satan for the destruction of the flesh, so that his spirit may be saved in the day of the Lord.” 

—1 Corinthians 5:1–5

“Deliver this man to Satan for the destruction of the flesh.” That is a hard word! It's an alarming way to describe removal from the church. Those who profess faith in Christ are baptized in his name. They belong to Christ and his Church. But to be removed from the Church and from Christ is to be handed over to Satan.

Even here, there is hope of restoration: “So that his spirit may be saved in the day of the Lord” (v. 5). But if that person’s heart remains hard, Christ is honored, and his Church is purified.

Why Does Church Discipline Work?

Jesus concludes with three powerful promises that motivate us to trust God to work through this redemptive process as we lean into the mess of sin and conflict. 
Jesus promises that the decisions and actions of the Church are backed by his heavenly power and authority. “Truly, I say to you, whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven” (Matthew 18:18).

The English translation doesn’t capture the Greek sense. It more literally says, “Whatever you bind … shall have been bound.” That is, the Church is not deciding for God, but responding to God and applying His Word. God has already bound (or loosed) in heaven, and the Church applies God’s Word on earth, declaring authoritatively what God forbids or permits.

Second, Jesus promises that when we prayerfully pursue wayward brothers and sisters, God himself will be at work. “Again I say to you, if two of you agree on earth about anything they ask, it will be done for them by my Father in heaven” (Matthew 18:19). In our unbelief, we are tempted to view prayer as passive and powerless. But notice the verbs: believers agree and ask from earth; the Father acts from heaven. Prayerful church discipline is a means of grace through which God asserts himself. 

Finally, Jesus promises his personal presence in the midst of his church. “For where two or three are gathered in my name, there am I among them” (Matthew 18:20). This is often quoted in small gatherings, and it’s not wrong for gathered Christians to comfort themselves with the assurance of Christ’s presence. But the context is the redemptive process of church discipline. The presence of Jesus in the midst of his church motivates us to lovingly confront sin, to pursue those who stray as Christ pursued us, and to forgive those who sin against us as God has forgiven us in Christ. And the presence of Jesus assures us that when we trust and obey him in this, we act with his blessing and approval.

Conclusion

Perhaps specific people have come to your mind this morning. You’ve been bitter toward someone who sinned against you. Or you have been concerned about someone you know is caught in serious sin. Trust Jesus by going to that person right away. Walk in this redemptive process he has given to us for our joy and for his glory.