Reference for Shevuot 70:18

אלא ה"ק וי"א זה קדש וזה הוא חול דמטתו ושמואל דאמר כי"א

All Kings mentioned in Daniel are secular except this which is sacred: Thou, O king, king of kings, unto whom the God of heaven hath given the kingdom, the power, and the strength, and the glory.<span class="x" onmousemove="('comment',' Dan. II, 37: Daniel would nor have called Nebuchadnezzar King of Kings; the verse is therefore interpreted thus: Thou, O king');">³¹</span> And some say, this also is sacred; it is said: My Lord, the dream be to them that hate thee, and the interpretation there to thine adversaries.<span class="x" onmousemove="('comment',' Dan IV. 16.');">³²</span> To whom does he say this?

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