Matthew 18:15-17—Moreover, if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother. But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established. And if he shall neglect to hear them, tell it unto the church: but if he neglects to hear the church, let him be unto thee as a heathen man and a publican.
This is the only passage in the New Testament that tells how to practically go about resolving a conflict between brothers in Christ. If we would follow it carefully, we would resolve many conflicts before they got to the point of being irreparable. Step one: The one who is offended goes to the one that offended him, one on one. 90% of issues will be resolved there. Usually, it is a misunderstanding or something that was done unintentionally. Do it quickly before bitterness takes root. Once you become embittered, no response will be sufficient to restore the relationship. Step two: If there is no resolution, the offending brother refuses to listen, then take along two or three witnesses. Ideally, there should only be five people at the most that know about the problem. We get into trouble when we start telling others and forming groups to support one another’s perception of what happened. Everyone wants to get support and sympathy, but the godly way is to keep those that know limited in an attempt to resolve the issue. Finally, if the brother refuses to listen, then take it to the church. Some interpret this to mean the elders of the congregation you attend. Others believe this means to bring it before the entire church body for resolution. If the brother refuses to listen to the church, (this assumes the church will be of one mind) treat him as a pagan or tax collector. This is one of Jesus’ few teachings about what the church needs to do. Jesus is referring to believers that gather to worship. It really did not exist at the time, so Jesus is looking into the future and specifically addressing a future need for His followers in a corporate setting. Then the question is how to treat a pagan or tax collector. Is Jesus saying how the Jews treated them or how He and His disciples did? One of them was a tax collector. Treat them as those in need of salvation, loving them, but not considering them a part of the body of the local church. That would still offer hope that things could be restored if they would repent.