Exodus 12:12-13:

For I will pass through the land of Egypt this night, and will smite 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.
And the blood shall be to you for a token upon the houses where ye are: and when I see the blood, I will pass over you, and the plague shall not be upon you to destroy you, when I smite the land of Egypt.

Notes on Exodus 12:12-13:

It is worth noting that the Israelites were commanded to sprinkle blood on the sides of their doors and above their doors.  This is an obvious symbol of the cross of Christ who shed His blood to redeem us from plagues and destruction.

Exodus 12:7:
And they shall take of the blood, and strike it on the two side posts and on the upper door post of the houses, wherein they shall eat it.

If the blood of the symbol of Jesus (Paul called Christ our Passover in 1 Corinthians 5:7) could keep a killer plague away from people, how much more should the blood of Christ Himself deliver us from all plagues?  You should note that the body of the Passover Lamb was to be eaten for physical strength.  Likewise, Christ’s body was broken to give our bodies physical strength.

This passage may alarm you because God says that He will kill a lot of people.  A plague was involved, as shown in this verse.  How was the plague propagated supernaturally?  Psalm 78:49-51 tells us that “evil angels” did it.  These were God’s angels that did evil to the Egyptians; they were not demons.  God killed a lot of people in the Old Testament when they tried to come against His people, so this was not a unique occurrence.

See also:

Forgiven People Can Be Healed
Healing and Atonement
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