Reference for Zevachim 203:16

וכל היכא דכתיב הלום לדורות הוא והא גבי שאול דכתיב (שמואל א י, כב) הבא עוד הלום איש הוא אין זרעו לא

R'Jannai said: Let the awe of kingship always be upon thee, for it is written, And all these thy servants shall come down unto me,<span class="x" onmousemove="('comment',' Ibid. XI, 8.');">¹⁸</span> but he did not say it of [Pharoah] himself.<span class="x" onmousemove="('comment',' Out of respect for royalty, though he knew that Pharoah himself would eventually appeal to him (ibid. XII, 30 seq.)');">¹⁹</span>

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