At the climax of the Song of the Sea, Israel proclaimed: "The Lord will reign for ever and ever" (Exodus 15:18). It is one of the most sweeping theological declarations in the entire Torah. But why did Israel choose this moment — standing on the far shore, watching the waters close over the Egyptian army — to declare God's eternal kingship?
The Mekhilta provides the answer from the very next verse: "For the horse of Pharaoh came with its chariot and its riders into the sea, and the Lord turned back upon them the waters of the sea" (Exodus 15:19). The declaration of eternal reign is directly caused by the drowning. God reigns forever because He drowned Pharaoh's cavalry.
The connection is not as obvious as it seems. Egypt was the greatest military power on earth. Pharaoh's chariot corps was the ancient equivalent of an armored division — fast, devastating, seemingly unstoppable. When those horses and chariots plunged into the sea and the waters crashed back upon them, it was not merely a military defeat. It was the destruction of the most powerful symbol of human sovereignty in the known world.
God's eternal kingship was proclaimed at the moment when human kingship was most dramatically exposed as temporary. Pharaoh — who claimed to be divine, who said "I do not know the Lord" — sent his greatest weapons into the sea, and the sea swallowed them. The contrast made God's sovereignty undeniable. If the mightiest king on earth cannot even keep his horses alive, then only one King reigns forever. Israel sang it because they had just watched the proof.