Halakhah for Zevachim 129:21

דבי רבי ישמעאל תנא בנוצתה בנוצה שלה קודרה בסכין כמין ארובה:

shall burn. and the blood thereof shall be drained out': now, can you really think that after he has burnt he returns and drains it?<span class="x" onmousemove="('comment',' That is obviously impossible!');">¹⁷</span> Rather it is to tell you: as haktarah is [done] on the top of the altar, so is the draining out on the top of the altar. How did he do this? He ascended the ascent and turned to the terrace, whence he proceeded to the south-east horn. Then he pinched off its head close by the neck, severed it, and drained [some] of its blood on the wall of the altar. If he did it below his feet<span class="x" onmousemove="('comment',' Stooping down,');">¹⁸</span> even a cubit, it is fit.<span class="x" onmousemove="('comment',' Because the red line, which demarcated the upper part of the altar from the lower, was a cubit below the terrace.');">¹⁹</span> R'Nehemiah and R'Eliezer B'Jacob maintained: It must essentially be done nought elsewhere but on the top of the altar. Wherein do they differ? - Abaye and Raba both said: They differ in respect of building a pyre on the terrace.<span class="x" onmousemove="('comment',' The first Tanna holds that this can be done, therefore the blood can be drained out even below the terrace. But R. Nehemiah and R. Eliezer b. Jacob hold that the haktarah must be done on the top of the altar itself; therefore the draining too must be done near there.');">²⁰</span> THEN HE TOOK THE BODY etc. Our Rabbis taught: And he shall take away its crop with the feathers thereof:<span class="x" onmousemove="('comment',' Lev. I, 16.');">²¹</span> that is the crop.<span class="x" onmousemove="('comment',' The Talmud translates the less familiar mur'ah by the more familiar zefek.');">²²</span> You might think that he cuts through with a knife and takes it;<span class="x" onmousemove="('comment',' Sc. the crop alone, without the skin and the feathers.');">²³</span> therefore it states, 'with the feathers thereof': [hence] he takes the plumage together with it. R'Abba Jose B'Hanan said: He takes it [the crop] together with the craw.<span class="x" onmousemove="('comment',' The thick muscular stomach of birds.');">²⁴</span> The school of R'Ishmael taught: 'With the feathers thereof' [means] with its [very] own feathers,<span class="x" onmousemove="('comment',' Not more than the feathers opposite the crop.');">²⁵</span> [hence] he cuts it [round] with a knife like a skylight.<span class="x" onmousemove="('comment',' He cuts the skin exactly opposite the crop, and then removes the crop, skin and feathers.');">²⁶</span>

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