Exodus 12:11; Exodus 12:21

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

21 Then Moses called all the elders of Israel and said to them, Go and select lambs for yourselves daccording to your clans, and kill the Passover lamb.