Exodus 12:5-9

Your lamb shall be an unblemished male a year old; you may take it from the sheep or from the goats.

You shall keep it until the fourteenth day of the same month, then the whole assembly of the congregation of Israel is to slaughter it at twilight.

Moreover, they shall take some of the blood and put it on the two doorposts and on the lintel of the houses in which they eat it.

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

Do not eat any of it raw or boiled at all with water, but rather roasted with fire, both its head and its legs along with its entrails.