Exodus 12:12-14

Darby Translation

¹² And I will go through the land of Egypt in that night, and 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 Jehovah.

¹³ And the blood shall be for you as a sign on the houses in which ye are; and when I see the blood, I will pass over you; and the plague shall not be among you for destruction, when I smite the land of Egypt.

¹⁴ And this day shall be unto you for a memorial; and ye shall celebrate it [as] a feast to Jehovah; throughout your generations [as] an ordinance for ever shall ye celebrate it.