Reference for Bekhorot 53:20

ואמר שמואל

and a priest who is a minor,<span class="x" onmousemove="('comment',' The woman herself being unclean through an uncleanness which issues from the body, and therefore only a minor but not an adult priest may eat it. And even an adult priest, if he bathes and purifies himself from pollution is considered as a minor in this respect. Another reason why it says 'a minor' is because a minor is not subject to pollution and thus did not become unclean. Still another reason is because hallah can be of a small quantity which is only sufficient for a minor, as the expression later on 'on the point of a shovel' indicates.');">¹⁷</span>

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