Mansur ibn Abi al-Aswad reported: I asked Al-A’mash, may Allah have mercy on him, about the saying of the Exalted, “’Thus, We appoint some oppress as allies of one another because of what they have earned,’ (6:129). What have you heard being said about it?” Al-A’mash said, “ I heard them say: If the people become corrupt, the worst of them will be appointed rulers over them.”
Source: Ḥilyat al-Awliyā’ 5/50
عَنْ مَنْصُور بْن أَبِي الْأَسْوَدِ رحمه الله قَالَ سَأَلْتُ الْأَعْمَشَ عَنْ قَوْلِهِ تَعَالَى وَكَذَلِكَ نُوَلِّي بَعْضَ الظَّالِمِينَ بَعْضًا بِمَا كَانُوا يَكْسِبُونَ مَا سَمِعْتَهُمْ يَقُولُونَ فِيهِ قَالَ سَمِعْتُهُمْ يَقُولُونَ إِذَا فَسَدَ النَّاسُ أُمِّرَ عَلَيْهِمْ شِرَارُهُمْ
5/50 حلية الأولياء وطبقات الأصفياء