Matthew 18:15-20 begins,
“If your brother sins, go and show him his fault when the two of you are alone. If he listens to you, you have regained your brother.” (NET)
“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.” (ESV, italics mine)
A quick survey of some of the most popular English translations show that the latter form is slightly more common. However, margin notes and commentaries reveal that the former (without the “against you”) is probably the original reading. I think that this better fits the overall context. When “against you” is included, the text suddenly introduces a thematic dichotomy: whereas the context thus far has been about community relationships as a whole in the kingdom of heaven, this addition marks an awkward and strange shift toward an individual grievance toward another individual – it would mark a drastic shift from concern about how others are treated, especially the “little ones,” to concern about how I’m treated. I think that the omission of the gloss keeps the context of these texts consistent with the thematic whole of the chapter.
The addition of εἰς σέ, “against you,” at this point in the majority of MSS and versions changes an altruistic concern about a brother’s spiritual danger into a personal grievance. That personal concern will be appropriate, and is made explicit, in Peter’s question in v. 21 (εἰς ἐμέ), which leads into the discussion of forgiveness for personal wrongs, but to introduce it here, where it is the brother’s welfare, not “your” interest, which is in focus, is premature; it is probably due to a mechanical reading back of the phrase from v. 21. The shorter reading of א and B (in agreement with the parallel in Luke 17:3, where there is less support for an added εἰς σέ) is thus to be preferred… (New International Commentary on the New Testament: Matthew, verse footnote)
Verses 15-17 have also traditionally been used as instructions for church discipline; i.e., if a church member is observed to be, or have been, committing a sin then these verses describe the procedure for confronting the offending member, up to and including a full church censure with a possible final result of excommunication (or disfellowshipping, depending on denominational tradition). While this may be a possible application, it is not the primary intent, once again returning to the observation that no “church hierarchy” or “church authority” has been invoked in the chapter thus far. Moreover we have already seen that such hierarchy or authority is discouraged and even denounced in earlier verses.
The singular pronouns of this paragraph make it very unlikely, however, that these verses should be understood as guidance specifically for church leaders… Commentators who use the formal language of ecclesiastical discipline or even “excommunication” in connection with v. 17 seem regularly to fail to notice the singular “you.” The person at risk is described as “your brother or sister” (adelphos, see 689, n.). This family language imports a note of personal care rather than objective censure… In view of such language we should be cautious about speaking in this context of “discipline,” if that term is understood to connote one person exercising authority over another… In view of such language we should be cautious about speaking in this context of “discipline,” if that term is understood to connote one person exercising authority over another. (NICNT: Matthew)
These texts might also be seen to speak to the sheep that is going astray in the immediately preceding verses. In other words, when a believer sees another member of the family going astray, these current verses are instructions on how to make the one going astray aware of their sin and to bring them back. And I think that is a more appropriate application than as the previously discussed “manual for church discipline.” But is this the only or the best way of reading this text?
Given the above, what then shall we make of this text?
The theme and context in the line of argument of this chapter is how some in the kingdom of heaven think they are greater than others, having more power, privilege, and authority, and in particular over the “little ones.” This very attitude and the actions based on them are “stumbling blocks” that have caused some of these “little ones” to go astray. Who is at greater fault here? Who has committed the greater sin? The warning given was that these would be better to cut off offending parts of themselves than to end up destroyed, and what they deserve is a millstone to be hung about them and they drowned than for them to destroy relationships in God’s kingdom.
I believe that the primary application for verses 15-20 is on those who are destroying others within the kingdom through their pursuit of “personal greatness.” These very same frequently intimidate those around them into saying and doing nothing about such sins. I think these verses are speaking to those who observe relationship destroying attitudes and actions happening, but are afraid to do anything about it. I think these verses are giving us permission, command, and authority to confront those who are power-seeking and abusive. These verses remind us that Christ himself will accompany those (c.f., vv. 19, 20) who actively look out for the welfare of the “little ones” to make sure they are not led or driven astray.
Yet in confronting those with self-aggrandizing and power-seeking attitudes, the goal is not to drive them away either. The ultimate goal is for all to be reconciled with one another. But we can’t make reconciliation happen if the offending party isn’t willing. In that case it is better for the parties to separate. Depending on the nature of the offense, further interaction may not be possible or desirable. Ultimate judgment is left to God.