Gregory the Great, on Exod 12:7

“And they shall take of the blood thereof, and put it upon both the side posts, and on the upper door posts of the houses, wherein they shall eat it.”

“For Moses says: "They shall take of the blood of the lamb and put it on both doorposts and on the lintels of the houses in which they shall eat it." All of which things indeed bring forth great edification for us, if they are examined through mystical interpretation. For who the blood of the lamb is, you have learned not now by hearing, but by drinking. This blood is placed on both doorposts when it is received not only by the mouth of the body but also by the mouth of the heart. For the blood of the lamb is placed on both posts when the sacrament of His passion is received by the mouth for Redemption, and is also contemplated with attentive mind for imitation. For he who receives the blood of his Redeemer in such a way that he does not yet wish to imitate His passion has placed the blood on only one post; it must also be placed above on the lintels of the houses. For what do we understand spiritually by houses except our minds, in which we dwell through thought? The lintel of this house is the very intention that presides over action. Therefore, whoever directs the intention of his thought toward the imitation of the Lord's passion places the blood of the lamb on the lintel of the house. Or certainly our houses are the bodies themselves, in which we dwell as long as we live. And we place the blood of the lamb on the lintel of the house because we bear the cross of His passion on our forehead.”

Imported from an open dataset — not yet checked against the printed edition.