¹⁵Now if your brother sins, go show him his fault, just between you and him. If he listens to you, you have won back your brother. ¹⁶But if he does not listen, take with you one or two others, so that ‘upon the mouths of two or three witnesses every matter be established.’ ¹⁷And if he refuses to listen to them, tell it to the assembly. And if he refuses to listen to the assembly, he should be regarded by you no differently than a gentile or a revenue agent.”
I agree with the UBS textual commentary that the phrase “against you” [if your brother sins against you] might have been added in order to harmonize this verse with the “against me” of v. 21 shortly thereafter where Peter asks, “How many times shall my brother sin against me and I forgive him?”
Peter was thinking of himself, but Jesus was thinking of the whole church and church discipline.
In my opinion, when it comes to variants in the Greek text of the New Testament, this is one of the most damaging, the longer reading containing “against you,” is damaging. Here is the practical situation. A brother is reported to have sinned, or be sinning. But not sinning against anyone in particular in that community. So no one goes and confronts him about it, because it was not involving them. The result is gossip, and then inflating of the original rumor, and even ultimately progressing to people “bearing false witness against their neighbor.” I know very well this scenario personally, because there are rumors about me sinning which are false rumors, but no one has come to me to talk to me about it. The rumor just keeps spreading, and takes on the appearance of truth since so many people have heard it.
Does anyone in that scenario want to “win back your brother”? If you have Christian love for your brother, you will go to him and talk to him about it, even if he did not sin against you in particular, because if the rumor is true, you want him to be restored. And if the rumor is not true, you do not want people spreading untrue things about your brother. This may not be scientific textual criticism, but I believe for practical and doctrinal and ecclesiological reasons that the shorter reading must be correct.
This is a very important, and very wonderful passage in the Bible, if applied correctly. Because it nips in the bud the problem of gossip. If you cannot get one or two others to agree to be witnesses with you against this brother regarding the accusation, then the accusation is probably not true. And if you do get someone to go with you, and you confront the brother, and he asks, when and were did you see me do this sin, and neither you nor your witnesses can answer that question, then that is another indication that the rumor is false. You have just been believing a rumor, started perhaps by some jealous person who has a personal problem with the accused. Then after finding that out, you have an obligation to rebuke anyone whom you hear repeating the false rumor.
You can download my translation of the Gospel of Matthew here.