Matzo reflects the rush to leave. Having no time, there was no time to wait for the bread to rise – thus the symbolism of matzo which is made with unleavened dough. Kosher law mandates that Jews avoid any grain that has come into contact with water and been allowed to ferment and rise – chametz in Hebrew. But the symbolism can be conceptualized another way, too. There is matzo called shmurah, also known as watched or guarded matzo. For each batch of shmurah the bakers mix, roll, and bake the matzo all within 18 minutes, guaranteeing no fermentation. In fact, for shmurah matzo the guarding against chametz begins not in the bakery but in the field, with rabbis overseeing the grain from harvest through milling.