Exodus 12:19
12:19 For seven days yeast must not be found in your houses, for whoever eats what is made with yeast – that person will be cut off from the community of Israel, whether a foreigner or one born in the land.
Exodus 13:7
13:7 Bread made without yeast must be eaten for seven days; no bread made with yeast shall be seen among you, and you must have no yeast among you within any of your borders.
Exodus 12:15
12:15 For seven days you must eat bread made without yeast. Surely on the first day you must put away yeast from your houses because anyone who eats bread made with yeast from the first day to the seventh day will be cut off from Israel.