Matthew 18:16-18

16But if you are unsuccessful, take one or two others with you and go back again, so that everything you say may be confirmed by two or three witnesses.

17If the person still refuses to listen, take your case to the church. Then if he or she won’t accept the church’s decision, treat that person as a pagan or a corrupt tax collector.

18“I tell you the truth, whatever you forbid on earth will be forbidden in heaven, and whatever you permit on earth will be permitted in heaven.