As one commentator notes, Judaism distinguishes between “neighbor” (a person of shared nationality) and “brother” (a person of shared religion). Here “your fellow believer” may be appropriate for brother. See comments at 5.22.
Against you may not have been an original part of the text. TC-GNT notes the possibility that the phrase was brought in by a later scribe under the influence of “against me” of verse 21. On the other hand, it points out that the omission could have been either intentional (so as to apply the passage to sin in general) or accidental (because of the similarity of sound between the last part of the Greek word “sin” and the Greek phrase “against you”). Therefore in the UBS Greek text the words are enclosed in square brackets to indicate that their presence in the text is disputed. The words are dealt with in a variety of ways in the translations, as the following sampling will illustrate: (1) they are included in Good News Translation, with a footnote indicating the possibility that they should be omitted; (2) they are omitted by New English Bible, with a footnote indicating the possibility that they should be included; (3) Revised Standard Version includes the words without a footnote; and (4) Bibel im heutigen Deutsch, 1st edition omits the words without a footnote.
In some languages sins is normally translated by a word or phrase that means to do wrong against God or disobey God. In such cases translators will have to render sins against you as “does wrong to you” or “does something evil against you.” Of course, if they choose to not include against you in the text, as discussed above, then translators will simply use the normal expression for sins.
The first step in winning back a disciple who has sinned is to go to him and show him his fault privately. The Greek verb translated tell … his fault is used only here in the Gospel of Matthew. In a more general sense it may mean “convince (someone) of something” or “point out something (to someone).” Both Revised Standard Version and Good News Translation: (“show him his fault”) may be too harsh, while New Jerusalem Bible (“have it out with him”) implies heated argument. The tone of the passage is better reflected in New English Bible (“take the matter up with him”) and Bibel im heutigen Deutsch, 1st edition (“speak with him about it”). The verb is used in the Septuagint translation of Leviticus 19.17; Revised Standard Version, there translating the Hebrew text, has “but you shall reason with your neighbor.” Other expressions that translators can use include “explain to him how he has sinned” and “talk with him about the matter.”
Between you and him alone is translated as a clause in Good News Translation: “But do it privately.” The German translations (Luther 1984, Zürcher Bibel, Die Bibel im heutigen Deutsch) utilize the idiom “under four eyes,” which means “privately” or “confidentially.” New English Bible translates “strictly between yourselves,” and New Jerusalem Bible “alone, between your two selves.”
This phrase between you and him alone may be restructured with the previous one, go and tell him his fault; for example, “Go and talk with him privately about his sin” or “Go to him, and when you are alone with him, you can discuss the matter.”
Listens to (so most all translations) means “pay attention to.” Although the verb itself may mean nothing beyond mere hearing, the context implies responsive and effectual listening. Thus “If he sees that you are right” or “If he admits that he has done wrong” are good translations.
You have gained your brother may be more effectively rendered “you have won him back as a brother” (Die Bibel im heutigen Deutsch). Good News Translation has “you have won your brother back.” In some languages one does not speak of gaining or winning a brother. “Then he will have become your brother again” or “Then you and he will once more be able to call each other brothers” are better expressions in these languages.
Quoted with permission from Newman, Barclay M. and Stine, Philip C. A Handbook on the Gospel of Matthew. (UBS Handbook Series). New York: UBS, 1988. For this and other handbooks for translators see here .