"[Harun] Aaron, my brother. Strengthen my back through him," meaning: my strength.
Muhammad said: It is said: "Azartu fulanan 'ala al-amr" (I helped so-and-so with the matter), meaning: I strengthened him for it. As for "wazartuhu" (I assisted him), it means: I became a vizier (helper/minister) for him."
﴿هَارُونَ أَخِي اشْدُدْ بِهِ أَزْرِي﴾ أَيْ: ظَهْرِي.
قَالَ مُحَمَّدٌ: يُقَالُ: أَزَرْتُ فُلَانًا عَلَى الْأَمْرِ؛ أَيْ: قَوَّيْتُهُ عَلَيْهِ، فَأَمَّا وَازَرْتُهُ: فَصِرْتُ لَهُ وزيرا.
