English: “And he shall offer from it his offering” — while still attached: he shall remove the devoted portions while they are still attached to the body, before he cuts the flesh.
In Sifra: “From it” is not mere wording. The fats of the goat shelamim (and parallel cases) are taken off the intact carcass; the butcher does not first joint the meat and then hunt for membranes.
Type of Learning
Custom (attached removal).
What Is Learned
Emurim are separated from the still-whole animal, not after the meat has been cut apart.