New Revised Standard Version
When Pharaoh stubbornly refused to let us go, the LORD killed all the firstborn in the land of Egypt, from human firstborn to the firstborn of animals. Therefore I sacrifice to the LORD every male that first opens the womb, but every firstborn of my sons I redeem.’

Contemporary English Version
The king stubbornly refused to set us free, so the LORD killed the first-born male of every animal and the first-born son of every Egyptian family. This is why we sacrifice to the LORD every first-born male of every animal and save every first-born son."

New American Bible
When Pharaoh stubbornly refused to let us go, the LORD killed every firstborn in the land of Egypt, the firstborn of human being and beast alike. That is why I sacrifice to the LORD every male that opens the womb, and why I ransom every firstborn of my sons.’

Douay-Rheims Bible
For when Pharao was hardened, and would not let us go, the Lord slew every firstborn in the land of Egypt, from the firstborn of man to the firstborn of beasts: therefore I sacrifice to the Lord all that openeth the womb of the male sex, and all the firstborn of my sons I redeem.

For when Pharao was hardened, and would not let us go, the Lord slew every firstborn in the land of Egypt, from the firstborn of man to the firstborn of beasts: therefore I sacrifice to the Lord all that openeth the womb of the male sex, and all the firstborn of my sons I redeem.

the Lord slew

Exodus 12:29 And it came to pass at midnight, the Lord slew every firstborn in the land of Egypt, from the firstborn of Pharao, who sat on his throne, unto the firstborn of the captive woman that was in the prison, and all the firstborn of cattle.

therefore I

Exodus 13:12 Thou shalt set apart all that openeth the womb for the Lord, and all that is first brought forth of thy cattle: whatsoever thou shalt have of the male sex, thou shalt consecrate to the Lord.