Reference for Bekhorot 53:18

ואמר שמואל

and this is the case only as regards eating, but as regards touching, there is no objection.<span class="x" onmousemove="('comment',' And although he makes the terumah unclean, we do not trouble, as there is no obligation to preserve it in a state of cleanliness.');">¹⁵</span>

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