Yoma 63: The Death of the Scapegoat
What happens when the kohen gadol goes to slaughter the goats? What if he does so outside of the Temple, which might be fine for the Azazel, but certainly not for the sin-offering. Designation of an animal for sacrifice is what makes the difference. In this case, through the lottery. [Who's Who: Hanan the Egyptian] Lining up the long beraita with his views. Plus, the unusual status of the Azazel goat - it doesn't really have a parallel.
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