What does Psalm 4:4 mean?
Some Bible teachers believe this verse and the next (Psalm 4:5) offer counsel to Absalom's men, David's enemies (2 Samuel 15:13–14). Verses 2 and 3 appear to be spoken to those foes, so this is possible (Psalm 4:2–3). Other interpreters apply verses 4 and 5 to David's followers. It seems more likely David is addressing his own men since they'd be more likely to heed his call to be in a right relationship with God. That would include remaining calm in the face of the opposition they faced from David's enemies (Psalm 3:1).David advises "Be angry, and do not sin." This is a classic example of words being difficult to translate easily from one language to another. The Hebrew root word translated as "be angry" here is ragaz, which most literally means "to tremble, shake, quake, or be agitated." Paul, citing the Septuagint Greek translation of this Psalm, also refers to the idea of anger (Ephesians 4:26). The meaning as implied in Psalm 4 is not merely about out-of-control wrath or fury. Anger, itself, is not a sin—but that emotion must be carefully controlled, as David recommends here.
David's men could easily let anger control their actions as they thought about their aggressors. Even righteous anger is not meant to lead us towards sin. Instead of risking sin, or giving in to it, David's men are advised to ponder their ways as they lie in bed and to be calm. Bedtime is a good time to search our hearts and confess the sins of the day. Doing so will help us enjoy a peaceful night's sleep instead of tossing and turning in an angry or worried state of mind.
If believers honor and trust in God, they do not need to be afraid of aggressive individuals or threatening circumstances. In Psalm 27:1 David proclaims, "The LORD is my light and my salvation; whom shall I fear? The LORD is the stronghold of my life; of whom shall I be afraid?"