Exodus 13:6-8

American Standard Version

⁶ Seven days thou shalt eat unleavened bread, and in the seventh day shall be a feast to Jehovah. ⁷ Unleavened 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. ⁸ And 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.