Leviticus 7:23
Say to the Israelites: do not eat any of the fat of cattle, sheep or goats. The prohibition on eating the fat of the three major domesticated animals — the animals used for the major offerings — is the congregation-facing statement of what the priestly regulations have communicated throughout: the fat of these animals belongs to God and is burned on the altar. The Israelite who does not offer to the altar still observes the same prohibition in their ordinary eating: the fat of cattle, sheep, and goats is not food for human consumption. The altar's regulation and the household's diet share the same underlying principle.