Exodus 12:6-10

6and you shall keep it until the fourteenth day of this month, when the whole assembly of the congregation of Israel shall kill their lambs at twilight.

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.