Шмот 3:5 Комментарий: Rashi, Ramban, Rashbam & Sforno

של means DRAW OFF and take off. It is of the same root as, (Numbers 19:5) “and the iron-head slippeth off (נשל) from the handle”; (Deuteronomy 28:40) “for thine olives shall drop off (ישל)‎”.

APPROACH NOT HITHER. Moses had not yet reached the highest degree of prophecy, for at Mount Sinai he drew near unto the thick darkness where G-d was.¹⁴⁸Further, 20:18. This also accounts for the hiding of his face [in this instance], for he had not yet reached that high [degree of prophecy of] which it was said of Moses, and the similitude of the Eternal doth he behold.¹⁴⁹Numbers 12:8.

של!, throw off!. The word is from the root נשל, meaning a form of removal, as in Deuteronomy 7,1 ונשל גוים רבים, “He dislodges many nations, etc.”