John Calvin Commentary Exodus 15:9

"The enemy said, I will pursue, I will overtake, I will divide the spoil; My desire shall be satisfied upon them; I will draw my sword, my hand shall destroy them." — Exodus 15:9 (ASV)

The enemy said. He relates the boast of Pharaoh not merely in exultation over him, but to magnify the miracle by which God gives over this wolf, intent on its prey, to destruction. But there is more force in the language when he introduces the Egyptians as speakers than if he had merely described their plans; for in this way the marvelous catastrophe more strikingly affects our minds when the Egyptians, as if brought onto the stage, not only trumpet forth their victory but also insolently give vent to their arrogance and cruelty.

Then, the Lord is introduced on the other side, dissipating their terrible audacity with a single blast. For from where did this great confidence come to the Egyptians—promising themselves that they would be satisfied with the spoils, and that, to put the people to death, they would need to do nothing more than draw their swords—except from the fact that they were very well armed against this unwarlike multitude? Therefore, God’s power shone forth more brightly when He swept them away by blowing with His wind.