Bamidbar 18:17

17 But the bechor of a cow, or the bechor of a sheep, or the bechor of a goat, thou shalt not redeem; they are kodesh; thou shalt sprinkle their dahm upon the Mizbe’ach, and shalt burn their fat for an offering made by eish, for a re’ach nichoach unto Hashem.

Bamidbar 18:17 Meaning and Commentary

Numbers 18:17

But the firstling of a cow, or the firstling of a sheep, or
the firstling of a goat, thou shalt not redeem
That is, shalt not take the redemption price for them, but the creatures themselves; which they, the priests, were to take for their own use:

they [are] holy;
separated to the Lord, and therefore not to be used in common by men, but were sacred to the Lord, or became the property of his priests; see ( Deuteronomy 15:19 ) ; how they were to be made use of follows:

thou shalt sprinkle their blood upon the altar;
for they were to be sacrificed, and their blood used as in other sacrifices:

and shalt burn their fat [for] an offering made by fire; for a sweet
savour unto the Lord;
as the fat of other sacrifices was, and particularly of the peace offerings, which were wholly eaten otherwise, ( Leviticus 7:31 ) .

Bamidbar 18:17 In-Context

15 Every thing that openeth the womb in all basar, which they bring unto Hashem, whether it be of adam or behemah, shall be thine; nevertheless the bechor haadam shalt thou surely redeem, and the bechor habehemah hateme’ah shalt thou redeem.

16 And those that are to be redeemed from a month old shalt thou redeem, according to thine evaluation, for the five silver shekelim, according to the shekel HaKodesh, which is twenty gerah.

17 But the bechor of a cow, or the bechor of a sheep, or the bechor of a goat, thou shalt not redeem; they are kodesh; thou shalt sprinkle their dahm upon the Mizbe’ach, and shalt burn their fat for an offering made by eish, for a re’ach nichoach unto Hashem.

18 And the basar of them shall be thine, like the breast of the tenufah and like the right thigh are thine.

19 All the terumot hakodashim, which the Bnei Yisroel offer unto Hashem, have I given thee, and thy banim and thy banot with thee, by a chok olam; it is a brit melach olam before Hashem unto thee and to thy zera with thee.