This was to be done by dipping a bunch of hyssop in the blood and thus sprinkling it upon the door frame (see Ex. 12:22). That this sprinkling of the blood of the paschal lamb was a symbol of the sacrifice and atonement made by the death of Jesus Christ is clearly implied in the NT (see 1 Peter 1:2; Rom. 5:8, 9; Heb. 9:13, 14; 13:12). It is to be noted that no blood was sprinkled on the threshold, perhaps in harmony with the thought that a man should not tread “under foot the Son of God,” nor count “the blood of the covenant, wherewith he was sanctified, an unholy thing” (Heb. 10:29). That the sprinkling with blood was to be regarded as an act of purification is evident from the fact that a hyssop branch was used for the purpose (Ex. 12:22). Sprinkling with hyssop is prescribed only in connection with purification (Lev. 14:49-52; Num. 19:18, 19; Ps. 51:7; PP 277).

 In Egypt the Israelites had no common altar, and for this reason the houses in which they assembled for the Passover were consecrated, and the individuals found in them were preserved when the destroyer passed by. Thus the sprinkling of blood on the doorposts and the lintel became a sign of deliverance. God promised to spare every house so marked through faith in this promise. After settlement in the land of Canaan the paschal lamb was to be slain and the Passover celebrated by all the people at one place, which God would choose, rather than in the various towns and villages (Deut. 16:5, 6). All males over 12 years of age were required to come to Jerusalem for this purpose. In Egypt, obviously, the Passover was celebrated under unusual circumstances. Whether the ritual of sprinkling blood at the door was perpetuated, perhaps in modified form, is not known.

 The blood represents the life (Lev. 17:11), and as the very essence of the sacrifice it was ever regarded as the special symbol of atonement, which the sacrifices typified. Since the paschal “lamb” was to redeem the “house,” which in Hebrew also means “family,” the sign of the atonement was to be conspicuously displayed.