Exodus 13:8

⁶  Seven days thou shalt eat unleavened bread, and in the seventh day shall be a feast to the LORD.

⁷  Unleavened bread shall be eaten seven days; and there shall no leavened bread be seen with thee, neither shall there be leaven seen with thee in all thy quarters.

⁸  And thou shalt show thy son in that day, saying, This is done because of that which the LORD did unto me when I came forth out of Egypt.

⁹  And it shall be for a sign unto thee upon thine hand, and for a memorial between thine eyes, that the LORD's law may be in thy mouth: for with a strong hand hath the LORD brought thee out of Egypt.

¹⁰  Thou shalt therefore keep this ordinance in his season from year to year.