The Song of the Sea contains multiple divine titles and attributes, each one apparently conveying a distinct aspect of God's power. The Mekhilta asks a pointed question: if all of these titles describe the same God, why does each one need to be stated separately? What does singling out each attribute accomplish?
The answer reveals something about the nature of divine warfare on behalf of Israel. When Israel requires it, God makes war for them. He does not merely permit them to fight. He fights on their behalf, deploying whatever aspect of His power the situation demands. Each title in the Song corresponds to a different mode of divine intervention, a different weapon in an infinite arsenal.
Then the Mekhilta pivots to the nations of the world, and the tone shifts to something almost apocalyptic. "Woe to the nations," the text declares, "what they hear with their ears." The nations are not merely warned. They are pitied. Because what they are hearing is that He who spoke and brought the world into being is destined to make war with them.
The creator of the universe is not a passive deity watching from a distance. He is an active combatant, and His capacity for warfare is identical to His capacity for creation. The same power that spoke galaxies into existence is the same power that will be directed against the enemies of Israel. The Mekhilta wants the reader to feel the weight of this equation. Creation and destruction flow from the same source. The nations who oppose Israel are not facing an army. They are facing the Author of reality itself.