A plea for divine justice rises from the aftermath of tragedy, asking God to hold the enemies accountable and punish them exactly as they treated the Israelites [צאינה וראינה, ביאור שטיינזלץ]. This appeal for justice contains a careful distinction between the internal intentions of the oppressors and their physical actions [פלגי מים].
On one level, the prayer addresses the evil thoughts and plans harbored by the enemies. On another level, it specifically demands a response for the actual deeds they committed. This division has a practical impact on the scope of the requested punishment. If God were to judge the enemies based on their hatred and destructive thoughts, the penalty would require their complete and endless destruction. Because the time for their final ruin has not yet arrived, the prayer intentionally focuses on their physical actions. By asking God to judge them based on what they actually did rather than their inner intentions, the punishment can be delivered swiftly and proportionally [אלון בכות].