Zevachim 77 - When Limbs of Sacrifices Get Mixed

If the limbs of a sin-offering intermingled with the limbs of a burnt-offering, then our problem is this: the limbs of a sin-offering should be eaten by the kohanim, and it is prohibited to burn them, while the limbs of a burnt-offering must be burnt, and it is prohibited to eat them.

Rabbi Eliezer says, "Let the kohen place all these limbs on the Altar, and I view the sin-offering (which is not supposed to be burned) as if it were mere wood." But the Sages say that the limbs must be left until the next morning, when they become invalidated as "leftovers", and then they can be burned together with all other invalidated offerings, in a place specially designated for this.

What is the reason of Rabbi Eliezer? After all, the Torah said, " They may not go on the Altar for satisfying aroma ..." Rabbi Eliezer says, "for satisfying aroma they should not go, but they can go on the Altar as fuel for fire."

Art: Winslow Homer - CampFire