The Prophet ﷺ said to Abu-Dhar, "Listen and obey (your chief) even if he is an Ethiopian with a head like a raisin."

قَالَ النَّبِيُّ ﷺ لأَبِي ذَرٍّ اسْمَعْ وَأَطِعْ وَلَوْ لِحَبَشِيٍّ كَأَنَّ رَأْسَهُ زَبِيبَةٌ