וַיֹּ֣אמֶר יְהוָה֮ אֶל־מֹשֶׁה֒ אֱמֹר֙ אֶֽל־אַהֲרֹ֔ן נְטֵ֣ה אֶֽת־מַטְּךָ֔ וְהַ֖ךְ אֶת־עֲפַ֣ר הָאָ֑רֶץ וְהָיָ֥ה לְכִנִּ֖ם בְּכָל־אֶ֥רֶץ מִצְרָֽיִם׃
At sinabi ng Walang-Hanggan kay Moises: “Sabihin mo kay Aaron: Iunat mo ang iyong tungkod at hampasin mo ang alabok ng lupa, at ito ay magiging mga kuto sa buong lupain ng Egipto.”
Rashi
אמר אל אהרן SAY UNTO AARON — The dust did not deserve to be smitten by Moses because it had protected him when he slew the Egyptian, for “he hid him in the sand”; and it was therefore smitten by Aaron (Tanchuma; Exodus Rabbah 10:7).
Chizkuni
והיו לכנים, “they will become vermin.” These are the kind of vermin that are products of the dust, but only rarely attack human beings. They emanated from their customary habitat, like the frogs and other plagues.
Rashbam
לכנם, different kinds of insects that cause man discomfort.