אָ֗ח נִפְשָׁ֥ע מִקִּרְיַת־עֹ֑ז ומדונים [וּ֝מִדְיָנִ֗ים] כִּבְרִ֥יחַ אַרְמֽוֹן׃
노엽게 한 형제와 화목하기가 견고한 성을 취하기보다 어려운즉 이러한 다툼은 산성 문빗장 같으니라
Rashi
A rebellious brother...of a strong city There is a brother who rebels against his brother and loses a strong city, e.g. Lot against Abraham and Esau against Jacob.
Rashi
and the quarrels are like the bolt of a castle The quarrel between them separates them forever, like a bolt with which they lock the gates of a castle, so that no one should enter it.