Blood On The Door
Most Relevant Verses
"For the LORD will pass through to smite the Egyptians; and when He sees the blood on the lintel and on the two doorposts, the LORD will pass over the door and will not allow the destroyer to come in to your houses to smite you.
"You shall take a bunch of hyssop and dip it in the blood which is in the basin, and apply some of the blood that is in the basin to the lintel and the two doorposts; and none of you shall go outside the door of his house until morning.
'The blood shall be a sign for you on the houses where you live; and when I see the blood I will pass over you, and no plague will befall you to destroy you when I strike the land of Egypt.