אמר אל אהרן קח מטך ונטה ידך על מימי מצרים
So begins the Ten Plagues that shook up the underpinnings of Egyptian arrogance and obstinacy. Hashem instructed Aharon to strike the waters; later, he struck the water from which emerged the frogs and then the earth which produced the lice. Why Aharon, and not Moshe? Chazal explain that the Nile River had protected Moshe Rabbeinu when he was an infant. It would have been wrong for him to serve as the instrument to inflict a plague on it. Likewise, the earth concealed the Egyptian that Moshe had slain. The Torah considers it wrong to show ingratitude even to an inanimate…