21 Then Moses called for all the elders of Israel and said unto them, Draw out and take lambs according to your families and sacrifice the passover.
22 And ye shall take a bunch of hyssop and dip [it] in the blood that [is] in the basin and touch the lintel and the two side posts with the blood that [is] in the basin; and none of you shall go out of the door of his house until the morning.
23 For the LORD will pass through smiting the Egyptians, and when he sees the blood upon the lintel and on the two side posts, the LORD will pass over that door and will not allow the destroyer to come in unto your houses to smite [you].