Exodus 12:17 in the King James Version
And ye shall observe the feast of unleavened bread; for in this selfsame day have I brought your armies out of the land of Egypt: therefore shall ye observe this day in your generations by an ordinance for ever.
Context
16 In the first day there shall be to you a holy convocation, and in the seventh day a holy convocation; no kind of work shall be done in them, except that which every man must eat, only that may be done by you.
17 You shall observe the feast of unleavened bread; for in this same day I have brought your armies out of the land of Egypt. Therefore you shall observe this day throughout your generations by an ordinance forever.
18 In the first month, on the fourteenth day of the month at evening, you shall eat unleavened bread, until the twenty first day of the month at evening.