The plagues came- one after another- ten of them, from G-d, and the last was Death. But the instruction came from YHVH for the eve of the Passover:
“Take care of (the lambs) until the fourteenth day of the month, when all the members of the community of Israel must slaughter them at twilight. Then they are to take some of the blood and put it on the sides and tops of the doorframes of the
houses where they eat the lambs. On that night I will pass through the land of Egypt and strike down every firstborn male, both man and beast, and I will execute judgment against all the gods of Egypt. I am YHVH. The blood shall be a sign for you on the houses where you live; and when I see the blood I will pass over you, and no plague will befall you to destroy you when I strike the land of Egypt” (Exodus 12).
It mattered not that you were old or young, pretty or ugly, nice or nasty, Hebrew or Egyptian- but Obedient to the instruction of YHVH. Whether you lived in a palace or a hovel, were a king or a slave, if you were obedient to such an odd and outlandish instruction, death would pass over your house.
And that obedience would be a sign not only for that generation, but of that which was to come at a future Passover. In Jerusalem, at the fullness of time, the Lamb of YHVH would be crucified, and his blood become the sign of deliverance from the death and slavery to sin for all future generations obedient to the sign.
On that first Passover the King of Egypt saw the first nine plagues fall upon his nation and, having survived them, ignored them with hardened heart. Finally, the tenth and final plague would enter into his very home to take the life of his firstborn son, to which he did surrender. As we prepare for this Passover of 2020, let us consider the realities that have come upon our planet, and harden not our hearts.