Numbers 3:10-13

YLT(i) 10 `And Aaron and his sons thou dost appoint, and they have kept their priesthood, and the stranger who cometh near is put to death.' 11 And Jehovah speaketh unto Moses, saying, 12 `And I, lo, I have taken the Levites from the midst of the sons of Israel instead of every first-born opening a womb among the sons of Israel, and the Levites have been Mine; 13 for Mine is every first-born, in the day of My smiting every first-born in the land of Egypt I have sanctified to Myself every first-born in Israel, from man unto beast; Mine they are; I am Jehovah.'