Reference for Chullin 175:29

כלל אמר רשב"ג

What is the difference between these two versions? - Where it is not absolutely necessary [to crush it],<span class="x" onmousemove="('comment',' Lit., 'it needs and does not need (to be crushed) '. According to the first version since it does not require to be crushed because it crumbles with the hand, it may be used for covering; according to the second version since it must be crushed even if only with the hand it may not be used for covering.');">¹⁰</span>

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