What does Psalm 55:9 mean?

Earlier in this psalm, David expressed deep anguish over a life-threatening situation (Psalm 55:1–8). Various clues in the psalm suggest the event in question is the rebellion of Absalom (2 Samuel 15:13–14). David's enemies—likely Absalom and his followers—had filled Jerusalem with evil and dissension. If this psalm is in relation to Absalom's rebellion, the "violence and strife" were likely part of turning the hearts of the people away from their king (2 Samuel 15:4–6). This attempted coup was aided by Ahithophel, a former counselor of David. When David heard this, he prayed that God would reduce the effectiveness of Ahithophel's advice (2 Samuel 15:31). The plea of this verse asks for something similar: that the enemy would have "divided" speech. This breakdown in communication would make it harder for them to plot against David.

Early in human history, men conspired to build a tall structure, presumably to establish their own legacy and to make them safe from another flood (Genesis 11:4). The tower is thought to have been a ziggurat: a pyramid-shaped structure with steps leading to a small temple at its top. However, God stopped the building project by confusing the builders' common language. Their communication ceased because suddenly they could not understand one another (Genesis 11:5–9).