ולא יראה לך חמץ ולא יראה לך שאור בכל גבולך
שמות יג ז
Do not see any Chametz in your dwellings on Pesach.
Males and females.
In the 1st, 2nd and 3rd Perek of Psachim
So we remember the miracles we saw in Egypt, and especially that Hashem took us out so quick that we needed to bake our dough as Matza.
If one transgresses
If he does an action on purpose, such as bringing Chametz into his dwelling he gets Malkos.