Exodus 12:18-20

12:18 In the first month, from the fourteenth day of the month, in the evening, you will eat bread made without yeast until the twenty-first day of the month in the evening. 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. 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 13:6-7

13:6 For seven days you must eat bread made without yeast, and on the seventh day there is to be a festival to the Lord. 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.

Leviticus 23:6

23:6 Then on the fifteenth day of the same month will be the festival of unleavened bread to the Lord; seven days you must eat unleavened bread.

Leviticus 23:14

23:14 You must not eat bread, roasted grain, or fresh grain until this very day, until you bring the offering of your God. This is a perpetual statute throughout your generations in all the places where you live.