Numbers 21:6

את הנחשים השרפים BURNING SERPENTS — so termed because they burn (cause fever in) a person through the poison of their fangs. וינשכו את העם AND THEY BIT THE PEOPLE — God said, as it were: Let the serpent which was punished for slanderous statements come and exact punishment from those who utter slander. — Let the serpent to which all kinds of food have one taste (that of earth; cf. Genesis 3:14 and Yoma 75a) come and exact punishment from these ingrates to whom one thing (the manna) had the taste of many different dainties (see Rashi 11:8) (Midrash Tanchuma, Chukat 19).

וַיְשַׁלַּ֨ח יְהֹוָ֜ה בָּעָ֗ם אֵ֚ת הַנְּחָשִׁ֣ים הַשְּׂרָפִ֔ים וַֽיְנַשְּׁכ֖וּ אֶת־הָעָ֑ם וַיָּ֥מׇת עַם־רָ֖ב מִיִּשְׂרָאֵֽל׃

And the Lord sent venomous serpents among the people, and they bit the people; and many people of Yisra᾽el died.