Exodus 11:5

“So I said to you, ‘Let My son go that he may serve Me’; but you have refused to let him go. Behold, I will kill your son, your firstborn.”’”

‘And I will go through the land of Egypt on that night and will strike down all the firstborn in the land of Egypt, both man and beast; and against all the gods of Egypt I will execute judgments—I am Yahweh.

Now it happened at midnight that Yahweh struck all the firstborn in the land of Egypt, from the firstborn of Pharaoh who sat on his throne to the firstborn of the captive who was in the dungeon, and all the firstborn of cattle.

“Then You performed signs and wonders against Pharaoh, Against all his servants and all the people of his land; For You knew that they acted presumptuously toward them, And made a name for Yourself as it is this day.

“Take the millstones and grind flour. Uncover your veil, strip off the skirt, Uncover the leg, cross the rivers.

“Two women will be grinding grain at the mill; one will be taken and one will be left.