وَنَحْنُ الْحَاكِمُونَ إِذَا أُطِعْنَا وَنَحْنُ الْعَازِمُونَ إِذَا عُصِينَا
We exercise authority when obeyed, and show determination when defied.
Al-ḥākimūna idhā uṭiʿnā and al-ʿāzimūna idhā ʿuṣīnā form parallel conditional units: obedience is contrasted with defiance.
Both uṭiʿnā and ʿuṣīnā are passive past verbs; al-ḥākimūn and al-ʿāzimūn are plural active participles. The balanced syntax presents the tribe as governing or acting resolutely according to circumstance.