'Door posts' in the Bible

They shall take some of the blood, and put it on the two doorposts and on the lintel, on the houses in which they shall eat it.

You shall take a bunch of hyssop, and 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 the morning.

For Yahweh will pass through to strike the Egyptians; and when he sees the blood on the lintel, and on the two doorposts, Yahweh will pass over the door, and will not allow the destroyer to come in to your houses to strike you.