15 And every thing that opens the womb of all flesh, whatever they bring to the Lord, whether man or beast, shall be your: only the firstborn of men shall be surely redeemed, and you shall redeem the firstborn of unclean cattle.
Numbers 18:15 Cross References - LXX2012
Exodus 13:2
2 Sanctify to me every firstborn, first produced, opening every womb among the children of Israel both of man and beast: it is mine.
Exodus 13:12-13
12 that you shall set apart every [offspring] opening the womb, the males to the Lord, every one that opens the womb out of the herds or among your cattle, as many as you shall have: you shall sanctify the males to the Lord.
13 Every [offspring] opening the womb of the ass you shall change for a sheep; and if you will not change it, you shall redeem it: every firstborn of man of your sons shall you redeem.
Exodus 22:29
29 You shall not keep back the first fruits of your threshing floor and press. The firstborn of your sons you shall give to me.
Exodus 34:20
20 And the firstborn of an ass you shall redeem with a sheep, and if you will not redeem it you shall pay a price: every firstborn of your sons shall you redeem: you shall not appear before me empty.
Leviticus 27:26-27
26 And every firstborn which shall be produced among your cattle shall be the Lord's, and no man shall sanctify it: whether calf or sheep, it is the Lord's.
27 But if he should redeem an unclean beast, according to its valuation, then he shall add the fifth part to it, and it shall be his; and if he redeem it not, it shall be sold according to its valuation.
Numbers 3:13
13 For every firstborn [is] mine; in the day in which I struck every firstborn in the land of Egypt, I sanctified to myself every firstborn in Israel: both of man and beast, they shall be mine: I [am] the Lord.
Numbers 3:46
46 And for the ransoms of the two hundred and seventy-three which exceed the Levites in number of the firstborn of the sons of Israel;