For the LORD will pass through to strike the Egyptians, and when he sees the blood on the lintel and on the two doorposts, the LORD will pass over the door and will not allow the destroyer to enter your houses to strike you. (Exodus 12:23 ESV)

The LORD was about to deliver the knockout punch to Pharaoh, forcing him to release his grip on the Lord’s people.  Nine plagues were not enough to break through Pharaoh’s hardened heart.  It would take the death of all the firstborn of Egypt to convince him “I AM”, of whom he was ignorant and unconcerned earlier, was THE GOD, to whom even the divine Pharaoh was to submit.  The LORD passed through Egypt, unleashing the destroyer on every house in Egypt, except those with the blood of a lamb on its lintel and doorposts.  Pharaoh had enough.  He let I AM’s people go.

On the night before He was crucified, Jesus began to reenact this ancient story with a new twist.  The destroyer was about to be unleashed again, but this time it would not be against the firstborn of Egypt or even the firstborn of Rome.  The destroyer would be turned loose on the Firstborn of God.  And it would be the blood of the Firstborn, applied to the heart of those confessing Jesus as Lord and believing that God had raised Him from the dead, that would provide protection from the destroyer.  And just as the body of the lamb, slain in the first Passover, was eaten by those protected by its blood; so Jesus’ body and blood, broken and poured out in the ultimate Passover, was and is consumed by those protected from the wrath to come, when the Firstborn returns in HIs glory.