וּלְבַ֥ב נִמְהָרִ֖ים יָבִ֣ין לָדָ֑עַת וּלְשׁ֣וֹן עִלְּגִ֔ים תְּמַהֵ֖ר לְדַבֵּ֥ר צָחֽוֹת׃
Rashi on Isaiah
And the heart of the hasty shall understand to know Not like now, that “this people’s heart is becoming fat” (ibid.).
Ibn Ezra on Isaiah
נמהרים The rash. Hasty in a foolish way. It is derived from מהר to be hasty.
Rashi on Isaiah
and the tongue of the stammerers, etc. Not like now, “for with distorted speech” (supra 28:11).