21 Then Moses called for all the elders of Israel, and said to them, Draw out, and take you a lamb, according to your families, and kill the passover.
22 And ye shall take a bunch of hyssop, and dip it in the blood that is in the basin, and strike the lintel and the two side-posts with the blood that is in the basin: and none of you shall go out at the door of his house till the morning.
23 For the LORD will pass through to smite the Egyptians; and when he seeth the blood upon the lintel, and on the two side-posts, the LORD will pass over the door, and will not suffer the destroyer to come in to your houses to smite you.