Whom have you appointed as your deputy over the people of the valley? He said: I have appointed Ibn Abza over them, ‘Umar said: Who is Ibn Abza? Nafiʼ said: One of our freed slaves. ‘Umar said: Have you appointed a freed slave over them? Nafi’ said: He has great knowledge of the Book of Allah, is well versed in the rules of inheritance (al­-fara'id) and is a (good) qadi (judge). 'Umar said. Indeed your Prophet ﷺ said, “Allah raises some people (in status) by means of this Book and brings others low by means of it.” (Using translation from Aḥmad 232)   

لَهُ عُمَرُ مَنِ اسْتَخْلَفْتَ عَلَى أَهْلِ الْوَادِي؟ فَقَالَ نَافِعٌ اسْتَخْلَفْتُ عَلَيْهِمْ ابْنَ أَبْزَى فَقَالَ عُمَرُ وَمَنْ ابْنُ أَبْزَى؟ فَقَالَ مَوْلًى مِنْ مَوَالِينَا فَقَالَ عُمَرُ فَاسْتَخْلَفْتَ عَلَيْهِمْ مَوْلًى؟ فَقَالَ يَا أَمِيرَ الْمُؤْمِنِينَ إِنَّهُ قَارِئٌ لِكِتَابِ اللَّهِ عَالِمٌ بِالْفَرَائِضِ فَقَالَ عُمَرُ أَمَا إن رَسُولَ اللَّهِ ﷺ قَدْ قَالَ «إِنَّ اللَّهَ يَرْفَعُ بِهَذَا الْكِتَابِ أَقْوَامًا وَيَضَعُ بِهِ آخَرِينَ»