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 29:2
29:2 and bread made without yeast, and perforated cakes without yeast mixed with oil, and wafers without yeast spread with oil – you are to make them using fine wheat flour.
Exodus 12:20
12:20 You will not eat anything made with yeast; in all the places where you live you must eat bread made without yeast.’”
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.