Exodus 12:7-13

7"Then they shall take some of the blood and put it on the two doorposts and the lintel of the houses in which they eat it.

8They shall eat the flesh that night, roasted on the fire; with unleavened bread and bitter herbs they shall eat it.

9Do not eat any of it raw or boiled in water, but roasted, its head with its legs and its inner parts.

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.