One of the questions in the ‘Mah Nishtana requires explanation. We ask, “Mah nishtana halayla hazeh mikol haleilos, shebichol haleilos onu ochlim chometz umatzah halayla hazeh kulo matzah”.
The Ababarbanel explains the question to mean as follows. Normally when a korbon todah is brought, it is accompanied by leavened breads and unleavened matzah. However, the korbon Pesach, which in essence is also a korbon todah, is only accompanied with matzah. (The korbon Pesach is similar to a korbon toda in that it is brought as a thanks for the nes of yitzias Mitzrayim.) Why does it not include leavened bread similar to any other korbon Todah?
We are familiar with how the seforim hakedoshim describe chometz. It represents the yetzer hara. Therefore, even a miniscule amount of chometz is prohibited. This is symbolic of the care one must give to not heed the yetzer hara whatsoever.
On Shavuos, there is a special korban called “Shtei Halechem”. This korbon contains chometz. This is the day of kabolas haTorah and the Torah is the only antidote against the yetzer hara. The shtei halechem containing chometz is symbolic of the Torah overcoming the chometz-the yetzer hara. Additionally, the Torah not only fends off the yetzer hara, but it can also transform his evil proclivities into positive inclinations.
Korbon Pesach whose original offering was in Mitzrayim, preceded kabolas haTorah. The absence of the Torah meant a lack of ammo to fight off the yetzer hara-the chometz. Therefore, chometz could not accompany the korban Pesach. Only matzah could go along with the korban Pesach.
The Ohr hachaim hakadosh points out that the exodus from Mitzrayim was with great haste- “bichipazon’. Since Klal Yisroel sunk to the abyss of tumah, almost descending to the fiftieth and lowest level of tumah, they needed to be hurried out lest they reach a point beyond return.
The Satmar Rebbi asks: In later generations we see that the Yidden unfortunately descended to the lowest of the low and recovered?
He profoundly points out that once Klal Yisroel received the Torah, they had the refuah to raise them even after sinking to the fiftieth level of tumah. In Mitzrayim they needed to be hurried out because they had not yet been gifted the Torah along with its powers to rejuvenate and purify the deepest impurities.
The prohibition against chometz is the issur to follow the yetzer hara. The unilateral defense against this menace, is involvement in limud haTorah.