Exodus 12:11

12:11 This is how you are to eat it – dressed to travel, your sandals on your feet, and your staff in your hand. You are to eat it in haste. It is the Lord’s Passover.

Exodus 12:21

12:21 Then Moses summoned all the elders of Israel, and told them, “Go and select for yourselves a lamb or young goat for your families, and kill the Passover animals.