Exodus 13:5-9

5And it shall be, when Jehovah shall bring thee into the land of the Canaanite, and the Hittite, and the Amorite, and the Hivite, and the Jebusite, which he sware unto thy fathers to give thee, a land flowing with milk and honey, that thou shalt keep this service in this month. 6Seven days thou shalt eat unleavened bread, and in the seventh day shall be a feast to Jehovah. 7Unleavened bread shall be eaten throughout the seven days; and there shall no leavened bread be seen with thee, neither shall there be leaven seen with thee, in all thy borders. 8And thou shalt tell thy son in that day, saying, It is because of that which Jehovah did for me when I came forth out of Egypt. 9And it shall be for a sign unto thee upon thy hand, and for a memorial between thine eyes, that the law of Jehovah may be in thy mouth: for with a strong hand hath Jehovah brought thee out of Egypt.