“Then they shall take some of the blood and put it on the two doorposts and the lintel of the houses in which they eat it.
Moses and Aaron here receive of the Lord what they were afterwards to deliver to the people concerning the ordinance of the passover, to which is prefixed an order for a new style to be observed in their months (Exo 12:1, Exo 12:2): This shall be to you the beginning of months.
Commenting on Exodus 12:1-20
And they shall take of the blood,.... Of the lamb, being received into a basin, Exo 12:22, and strike it on the two side posts; with a bunch of hyssop dipped into it: and on the upper doorpost of the houses, wherein they shall eat it; but not on the posts of those houses, the inhabitants of which joined with their neighbours in eating it...
take of the blood, and strike it on the two side-posts, &c.--as a sign of safety to those within. The posts must be considered of tents, in which the Israelites generally lived, though some might be in houses. Though the Israelites were sinners as well as the Egyptians, God was pleased to accept the substitution of a lamb--the blood of which, being seen sprinkled on the doorposts, procured them mercy.