וַיִּסְע֞וּ מֵהֹ֤ר הָהָר֙ דֶּ֣רֶךְ יַם־ס֔וּף לִסְבֹ֖ב אֶת־אֶ֣רֶץ אֱד֑וֹם וַתִּקְצַ֥ר נֶֽפֶשׁ־הָעָ֖ם בַּדָּֽרֶךְ׃
And they journeyed from mount Hor by the way to the Red Sea, to compass the land of Edom; and the soul of the people became impatient because of the way.
Find Mishnaic references to Numbers 21:4: , passages from the 63 tractates of the Mishnah.