Reference for Bekhorot 58:23

ות"ק

If we must not purchase washed wool<span class="x" onmousemove="('comment',' Where one might have said that he would not take the trouble to wash the wool if it came from a firstling, for fear that the Rabbis might hear of the case and he would as a result have to forfeit it.');">¹⁰</span>

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