For all the firstborn of the children of Israel [are] mine, [both] man and beast: on the day that I smote every firstborn in the land of Egypt I sanctified them for myself.
Berean Study Bible (BSB) - Numbers 8:17 >For every firstborn male in Israel is Mine, both man and beast. I set them apart for Myself on the day I struck down all the firstborn in the land of Egypt.