Mat 18:15 "If your brother sins, go and show him his fault in private; if he listens to you, you have won your brother. Mat 18:16 "But if he does not listen to you, take one or two more with you, so that BY THE MOUTH OF TWO OR THREE WITNESSES EVERY FACT MAY BE CONFIRMED. Mat 18:17 "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. Mat 18:18 "Truly I say to you, whatever you bind on earth shall have been bound in heaven; and whatever you loose on earth shall have been loosed in heaven.
This is a difficult subject. If you feel that you have witnessed your Christian Brother in a sin you should tell him so. Providing he or she listens to you without getting mad at you and he or she recognizes the sin you have kept a friend. If the friend brushes you off and without gossiping you bring another couple of Christian Brothers to discuss it with him hopefully he or she repents. The next step is to bring it to the church. If he or she still refuses the churches advice the church should discharge that person from their membership. This is a foreign concept in this modern age. Most of us claim our rights to do this or that as long as it is not illegal. So what sins qualify? Examples gossip, or cheating on a spouse or whatever you know is a sin that God would condemn. You are trying to save a person’s soul. I have had personal experiences with this and some went well and others not so good. It is scary are to move into. You have to try to help the person live a more Christian life.
Mat 18:19 "Again I say to you, that if two of you agree on earth about anything that they may ask, it shall be done for them by My Father who is in heaven. Mat 18:20 "For where two or three have gathered together in My name, I am there in their midst."
These two verses are associated with the previous 4 verses. The LANTC1 says it the best: In context, the application of this verse applies to matters of church discipline. Two people agree, and God stands among them as they work through their disagreement. If the matter must go before the church, God is there helping those in agreement to deal with the sinning member as they ought. Indeed, God may be using the people to “chase down the lost sheep,” so to speak, and bring him or her back “into the fold.”
This whole 6 verse are meant to bring a lost sheep back into the fold. This day's writing may seem short but I would like you to think about the ramifications and your obligations to your Christian Brother. When ever you do something like these set of verses say, you are stepping out on a limb. Pray about what you are going to do and move forward with what God is telling you to do.
1 Life Application New Testament Commentary