Exodus 12:10-14

10And you shall let none of it remain until the morning; anything that remains until the morning you shall burn.

11In this manner you shall eat it: with your belt fastened, your sandals on your feet, and your staff in your hand. And you shall eat it in haste. It is the Lord's Passover.

12For I will pass through the land of Egypt that night, and I will strike all the firstborn in the land of Egypt, both man and beast; and on all the gods of Egypt I will execute judgments: I am the Lord.

13The blood shall be a sign for you, on the houses where you are. And when I see the blood, I will pass over you, and no plague will befall you to destroy you, when I strike the land of Egypt.

14"This day shall be for you a memorial day, and you shall keep it as a feast to the Lord; throughout your generations, as a statute forever, you shall keep it as a feast.