Psalm 78:51

“Reuben, you are my firstborn; My might and the beginning of my vigor, Preeminent in dignity and preeminent in strength.

and all the firstborn in the land of Egypt shall die, from the firstborn of the Pharaoh who sits on his throne, even to the firstborn of the servant-girl who is behind the millstones; and all the firstborn of the cattle.

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.

Remember His wondrous deeds which He has done, His miraculous signs and the judgments uttered by His mouth,

“They refused to listen, And did not remember Your wondrous deeds which You did among them; So they became stiff-necked and gave themselves a chief to return to their slavery in Egypt. But You are a God of lavish forgiveness, Gracious and compassionate, Slow to anger and abounding in lovingkindness; And You did not forsake them.

They set forth the words of His signs among them, And miracles in the land of Ham.

He struck the firstborn of Egypt, From man to beast.

To Him who struck the Egyptians through their firstborn, For His lovingkindness endures forever,