Bible Verses about Blood on Doorposts
Now you shall keep it until the fourteenth day of the same month. Then the whole assembly of the congregation of Israel shall kill it at twilight. And they shall take some of the blood and put it on the two doorposts and on the lintel of the houses where they eat it.
"For I will pass through the land of Egypt on that night, and will strike all the firstborn in the land of Egypt, both man and beast; and against all the gods of Egypt I will execute judgment: I am the LORD. Now the blood shall be a sign for you on the houses where you are. And when I see the blood, I will pass over you; and the plague shall not be on you to destroy you when I strike the land of Egypt.
And you shall take a bunch of hyssop, dip it in the blood that is in the basin, and strike the lintel and the two doorposts with the blood that is in the basin. And none of you shall go out of the door of his house until morning. For the LORD will pass through to strike the Egyptians; and when He sees the blood on the lintel and on the two doorposts, the LORD will pass over the door and not allow the destroyer to come into your houses to strike you.
It will come to pass when you come to the land which the LORD will give you, just as He promised, that you shall keep this service. And it shall be, when your children say to you, "What do you mean by this service?" that you shall say, "It is the Passover sacrifice of the LORD, who passed over the houses of the children of Israel in Egypt when He struck the Egyptians and delivered our households."" So the people bowed their heads and worshiped.