“Koraḥ, son of Yitzhar son of Kehat son of Levi, and Datan and Aviram, sons of Eliav, and On, son of Pelet, sons of Reuben, took” (Numbers 16:1). “Koraḥ, son of Yitzhar son of Kehat…” – this is what is written: “A treacherous [nifsha] brother is worse than a fortified city” (Proverbs 18:19). This is Koraḥ, who entered into a dispute with Moses, rebelled, and was stripped of the honor that he had acquired.
Nifsha is nothing other than rebellion, just as it says: “The king of Moav rebelled [pasha] against me” (II Kings 3:7). “And strife is like the bolts of a palace [armon]” (Proverbs 18:19) – the earth elevated its bolts1The midrash is explaining that the doors and bolts of the depths of the earth will open and swallow him. due to the iniquity relating to armon,2Armon means palace, and is deemed as referring to God and to Moses. that he entered into a dispute with Moses and with the Omnipresent.