בַּיּ֣וֹם הַה֗וּא נְאֻם֙ יְהוָ֣ה צְבָא֔וֹת תָּמוּשׁ֙ הַיָּתֵ֔ד הַתְּקוּעָ֖ה בְּמָק֣וֹם נֶאֱמָ֑ן וְנִגְדְּעָ֣ה וְנָפְלָ֗ה וְנִכְרַת֙ הַמַּשָּׂ֣א אֲשֶׁר־עָלֶ֔יהָ כִּ֥י יְהוָ֖ה דִּבֵּֽר׃ (ס)
In that day, saith the LORD of hosts, shall the peg that was fastened in a sure place give way; and it shall be hewn down, and fall, and the burden that was upon it shall be cut off; for the LORD hath spoken it.
Rashi on Isaiah
shall the peg...move (This alludes to) the greatness of Shebna.
Ibn Ezra on Isaiah
The nail, etc. Shebna, who thought himself a nail fixed in a strong place.
Rashi on Isaiah
and the burden which is upon it shall be cut off His family members and his company who depend on him and who hang upon him the vessels of their glory. And since he likened him to a peg, he likened those who boast about him and rely on him, to a burden loaded on the peg. Some interpret it: And the prophecy prophesied about him shall be fulfilled.