אָ֗ח נִפְשָׁ֥ע מִקִּרְיַת־עֹ֑ז ומדונים [וּ֝מִדְיָנִ֗ים] כִּבְרִ֥יחַ אַרְמֽוֹן׃
A brother offended is harder to be won than a strong city; And their contentions are like the bars of a castle.
Read kabbalistic (mystical) interpretation of Proverbs 18:19: and classical mystical sources.