The sense of the first Hebrew verb is disputed; the root meaning seems to be “be excited, perturbed,” whether with fear, anger, or joy. The Septuagint takes it in the sense of anger, and it is in this sense that the passage is quoted in Ephesians 4.26; and that is how Revised Standard Version, New English Bible, Zürcher Bibel, and Bible en français courant have translated it here. But most modern translators and commentators take it in the sense of fear: Briggs, Kirkpatrick, Weiser, New American Bible, New Jerusalem Bible, and others. Certainly this seems more appropriate as a warning to the psalmist’s enemies. If a translator chooses the meaning of anger, the sense of the line must be something like “If you are angry, do not sin” (Bible en français courant) or “Don’t let your anger lead you into sin.”
In many languages it is unnatural to command someone to experience an emotional state such as fear or anger. For this reason the relation between the emotion and the following command is not readily apparent without recasting the anger part as a dependent clause. Many languages express fear in terms of such figures as “trembling heart” or “breath departed.” Here also the rendering may be more meaningful with a subordinate clause expressing the fear; for example, “even when your heart trembles from fear of God’s punishment, do not sin” or “although you are afraid of what might happen to you, do not let this make you sin.”
The next line is literally “talk in your hearts on your beds and be silent,” which is an advice to the psalmist’s enemies to meditate quietly and in private on what the psalmist is saying. New International Version “when you are on your beds, search your hearts and be silent.” The word beds (or, “couches”) may imply nighttime, or else simply privacy (so Weiser); and the verb translated “be silent” may mean “be inactive,” that is, don’t do anything. New Jerusalem Bible has “sigh.”
Some languages express meditation and reflection in ways very close to the Hebrew form. But the same expression in other languages would imply that such a person is mentally unstable. It is therefore sometimes necessary to say “think about these words” or “remember these words.” In many cultures practically the only privacy a person has is at night on his bed. The entire sentence can often be rendered “When you lie down on your bed at night, think about these words and be silent.”
Quoted with permission from Bratcher, Robert G. and Reyburn, William D. A Handbook on the Book of Psalms. (UBS Helps for Translators). New York: UBS, 1991. For this and other handbooks for translators see here .