(15) Every thing that openeth the matrix . . . --(See Leviticus 27:6; Leviticus 27:26-27.) Five shekels was the redemption-price paid for each of the firstborn who were not redeemed by the Levites (Numbers 3:47).

18:8-19 All believers are spiritual priests, and God has promised to take care of them. Godliness has the promise of the life that now is. And from the provision here made for the priests, the apostle shows that it is the duty of christian churches to maintain their ministers. Scandalous maintenance makes scandalous ministers. The priests were to be wholly devoted to their ministry, not diverted from it, or disturbed in it, by worldly care or business. Also, that they might be examples of living by faith, not only in God's providence, but in his ordinances. The best should be offered for the first-fruits unto the Lord. Those who think to save, by putting God off with the refuse, deceive themselves, for God is not mocked.Every thing that openeth the matrix in all flesh,.... The firstborn of every creature:

which they bring unto the Lord; as they were obliged, he claiming it as his own, Exodus 13:2,

whether it be of men or beasts, shall be thine; every firstborn of either, being the Lord's, became the priest's by his gift:

nevertheless, the firstborn of man shalt thou surely redeem; that is, take the redemption price for it, which was five shekels, as in Numbers 18:16; for the original proprietor was, strictly speaking, the redeemer, and paid the money, and the priest was the receiver, to whom it was paid; see Exodus 13:13,

and the firstlings of unclean beasts shall thou redeem; with lambs, as an ass, which is put for unclean beasts, is ordered to be redeemed with a lamb, or its neck to be broken, Exodus 13:13; the Africans, the shepherds among them, as Herodotus relates (k), of their firstlings they cut off the ear of the beast and throw it over a house, and then turn its neck back, for they worship only the sun and moon; which seems to be an imitation of this law.

(k) Melpomene, sive, l. 4. c. 188.