This saying is made up of four lines, in which there are three negative commands. The commands are warnings against making false accusations and taking revenge on others. The setting may be a court of law or local tribunal.

“Be not a witness against your neighbor without cause”: The main part of this line is literally “Do not be a witness for nothing,” in which “for nothing” means “when he has given you no reason for. . .”; see the comments on 3.30. Contemporary English Version takes the expression to mean “who isn’t guilty,” but this is not quite the same thing. “Your neighbor”, as in 6.1, means “another person” or “anyone” rather than a person who lives nearby; so Good News Translation correctly says “Do not give evidence against others without good reason.”

“And do not deceive with your lips”: This would seem to say simply “don’t tell lies” (Contemporary English Version “don’t ever tell a lie”). But if the reference is to the same setting as in the previous line, the sense must be something like “and don’t give false [or, misleading] evidence.” So Good News Translation has “[Don’t] say misleading things about them” and Revised English Bible “or misrepresent him in your evidence.” In one translation this is expressed as “Don’t tell lies to deceive the court.”

“Do not say”: This can be understood in two ways; “say” may mean that the person speaks aloud to other people, or it may mean that he says the words to himself. In the second case we could translate “Do not think. . ..” The whole sentence is a warning against taking revenge.

““I will do to him as he has done to me””: Since “him” and “the man” can only refer back to “neighbor” in the first line of the saying, “I will do to him” must refer to the action described there. New Jerusalem Bible renders this clause “I will treat my neighbor as my neighbor treated me.” So this sentence suggests that the person wants to give false evidence against someone else in order to take revenge (“pay the man back”) for a past wrong.

““I will pay the man back for what he has done””: This repeats in other words the thought of the previous clause. The two clauses may be combined; however, this second clause (literally “I will give back to the man according to his action”) adds something to the meaning by expressing a view about retaliation which is common in many societies, and translators may wish to render this in the terms that are used in their languages. In English, for example, we may say “I’ll get even. . .” (Good News Translation, Contemporary English Version) or “I am paying off an old score” (Revised English Bible).

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Proverbs. (UBS Helps for Translators). New York: UBS, 2000. For this and other handbooks for translators see here .