Reference for Kiddushin 64:12

רבי שמעון בן אלעזר אומר מנין לזקן שלא יטריח ת"ל זקן ויראת איסי בן יהודה אומר מפני שיבה תקום אפילו כל שיבה במשמע

I might think that one must rise up before him out of a privy or a bathhouse, therefore it is written 'thou shalt rise up and thou shalt honour', [implying] I ordered to rise up only in a place where it confers honour. I might think that one may shut his eyes as though he has not seen him: therefore it is taught,. thou shalt rise up, and thou shalt fear thy God:<span class="x" onmousemove="('comment',' Ibid.');">²⁶</span>

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