Reference for Pesachim 154:8

השתא לימא מתני' דלא כרבי יהושע דכיון דאמר בעינן תרתי וציץ אאכילות לא מרצה היכי אתי בטומאה

are not indispensable [to the eating of the flesh] , yet when available are indispensable;<span class="x" onmousemove="('comment',' The flesh may not be eaten until the emurim are burnt on the altar, v. supra 59b.');">⁹</span> then the blood, which if not available is indispensable, if available how much the more is it indispensable! And R'Eliezer?<span class="x" onmousemove="('comment',' Does he not accept this argument?');">¹⁰</span>

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