ולא יאכל חמץ
שמות יג ג
Do not eat any leavened grain product on Pesach.
Males and females.
In the 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
On purpose he gets Kareis, by accident he must bring a Chatos.