Exodus 12:13-28

The blood on the doorposts will be a sign to mark the houses in which you live. When I see the blood, I will pass over you and will not harm you when I punish the Egyptians. You must celebrate this day as a religious festival to remind you of what I, the LORD, have done. Celebrate it for all time to come.” The LORD said, “For seven days you must not eat any bread made with yeast — eat only unleavened bread. On the first day you are to get rid of all the yeast in your houses, for if anyone during those seven days eats bread made with yeast, he shall no longer be considered one of my people. On the first day and again on the seventh day you are to meet for worship. No work is to be done on those days, but you may prepare food. Keep this festival, because it was on this day that I brought your tribes out of Egypt. For all time to come you must celebrate this day as a festival. From the evening of the fourteenth day of the first month to the evening of the 21st day, you must not eat any bread made with yeast. For seven days no yeast must be found in your houses, for if anyone, native-born or foreign, eats bread made with yeast, he shall no longer be considered one of my people.” Moses called for all the leaders of Israel and said to them, “Each of you is to choose a lamb or a young goat and kill it, so that your families can celebrate Passover. Take a sprig of hyssop, dip it in the bowl containing the animal's blood, and wipe the blood on the doorposts and the beam above the door of your house. Not one of you is to leave the house until morning. When the LORD goes through Egypt to kill the Egyptians, he will see the blood on the beams and the doorposts and will not let the Angel of Death enter your houses and kill you. You and your children must obey these rules for ever. When you enter the land that the LORD has promised to give you, you must perform this ritual. When your children ask you, ‘What does this ritual mean?’ you will answer, ‘It is the sacrifice of Passover to honour the LORD, because he passed over the houses of the Israelites in Egypt. He killed the Egyptians, but spared us.’ ” The Israelites knelt down and worshipped. Then they went and did what the LORD had commanded Moses and Aaron.