Reference for Chullin 252:20

אלא מעתה כוליא בחלבה לא תטמא

In that case the kidney [of a carcass], so long as it is surrounded with fat, should not convey uncleanness?<span class="x" onmousemove="('comment',' For the fat itself is clean, v. Pes. 231.');">¹⁰</span>

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