17 But the firstling of a cow, or the firstling of a sheep, or the firstling of a goat, thou shalt not redeem; they are holy: thou shalt sprinkle their blood upon the altar, and shalt burn their fat for an offering made by fire, for a sweet savor to the LORD.
Numbers 18:17 Cross References - Webster
Exodus 29:16
16 And thou shalt slay the ram, and thou shalt take his blood, and sprinkle it around upon the altar.
Leviticus 3:2-5
2 And he shall lay his hand upon the head of his offering, and kill it at the door of the tabernacle of the congregation: and Aaron's sons the priests shall sprinkle the blood upon the altar round about.
3 And he shall offer of the sacrifice of the peace-offering, an offering made by fire to the LORD; the fat that covereth the inwards, and all the fat that is upon the inwards,
4 And the two kidneys, and the fat that is on them, which is by the flanks, and the caul above the liver, with the kidneys, it shall he take away.
5 And Aaron's sons shall burn it on the altar, upon the burnt-sacrifice which is upon the wood that is on the fire: it is an offering made by fire, of a sweet savor to the LORD.
Deuteronomy 15:19-22
19 All the firstling males that come of thy herd and of thy flock thou shalt sanctify to the LORD thy God: thou shalt do no work with the firstling of thy bullock, nor shear the firstling of thy sheep.
20 Thou shalt eat it before the LORD thy God year by year in the place which the LORD shall choose, thou and thy household.
21 And if there is any blemish in it, as if it is lame, or blind, or hath any ill blemish, thou shalt not sacrifice it to the LORD thy God.
22 Thou shalt eat it within thy gates: the unclean and the clean person shall eat it alike, as the roebuck, and as the hart.