Exodus 13
6 Ref For seven days let your food be unleavened cakes; and on the seventh day there is to be a feast to the Lord.
7 Ref Unleavened cakes are to be your food through all the seven days; let no leavened bread be seen among you, or any leaven, in any part of your land.
8 Ref And you will say to your son in that day, It is because of what the Lord did for me when I came out of Egypt.
9 Ref And this will be for a sign to you on your hand and for a mark on your brow, so that the law of the Lord may be in your mouth: for with a strong hand the Lord took you out of Egypt.
10 Ref So let this order be kept, at the right time, from year to year.