When Yithro, the father-in-law of Moses, heard about everything that had happened at the Red Sea, he made a remarkable declaration: "Now I know that greater is the Lord than all the gods" (Exodus 18:11). The Mekhilta unpacks the weight of that phrase "now I know." Yithro was not encountering God for the first time. He had already recognized the God of Israel in the past. But the events at the sea elevated his understanding to an entirely new level.
What specifically convinced Yithro? The verse continues with a phrase the Mekhilta reads as the key: "For they were destroyed by the very thing whereby they devised evil against them." The Egyptians had used water as their weapon of genocide — drowning Israelite baby boys in the Nile. God responded by destroying them with water at the Red Sea. The punishment mirrored the crime exactly.
This principle of measure-for-measure justice — middah k'neged middah — is what magnified God's name throughout the world. Yithro, a Midianite priest who had worshipped other gods and investigated every form of idolatry, recognized in this perfect symmetry something no other deity could achieve. Other gods might be powerful. Only the God of Israel was just with such precision that the very instrument of cruelty became the instrument of retribution. The drowning of the Egyptians was not random divine wrath — it was a mirror held up to their own wickedness.