Exodus 12:29
And it came to pass, that at midnight the LORD smote all the firstborn in the land of Egypt, from the firstborn of Pharaoh that sat on his throne to the firstborn of the captive that was in the dungeon; and all the firstborn of cattle.
Nave's Topical Index—AKJV

Psalm 78:51
And smote all the firstborn in Egypt; the chief of their strength in the tabernacles of Ham:
Nave's Topical Index—AKJV

Psalm 105:36
He smote also all the firstborn in their land, the chief of all their strength.
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Psalm 136:10
To him that smote Egypt in their firstborn: for his mercy endures for ever:
Nave's Topical Index—AKJV