Êxodo 12:15

15 For seven days you are to eat bread made without yeast. On the first day remove the yeast from your houses, for whoever eats anything with yeast in it from the first day through the seventh must be cut off from Israel.

15 For seven days let your food be unleavened bread; from the first day no leaven is to be seen in your houses: whoever takes bread with leaven in it, from the first till the seventh day, will be cut off from Israel.