Reference for Chullin 54:4

חופה את הפדר על בית השחיטה ומעלהו וזהו דרך כבוד של מעלה

Another Tanna derives it from the following Baraitha: It is written: This is the law of cattle and of birds.<span class="x" onmousemove="('comment',' Lev. XI. 46. The passage deals with the laws of uncleanness of the carcasses of animals.');">²</span>

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