Reference for Kiddushin 63:7

וכי הא דרבה בר רב הונא דרב הונא קרע שיראי באנפי רבה בריה אמר איזול איחזי אי רתח אי לא רתח ודלמא רתח וקעבר (ויקרא יט, יד) אלפני עור לא תתן מכשול דמחיל ליה ליקריה

But if you say, at the son's expense, he is thus found to fulfil his obligations with what belongs to the poor? - This refers only to an extra quantity.<span class="x" onmousemove="('comment',' The son must furnish him with an average quantity of food, if his father needs more, he may give him poor tithe.');">⁹</span> If so, could it be taught thereon, R'Judah said: A curse may alight upon him who feeds his father with poor tithe! But if the reference is to an extra quantity, what does it matter?<span class="x" onmousemove="('comment',' Surely there is no objection to it!');">¹⁰</span>

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