It wasnarrated that Isma'il bin Abu Khalid said:
"I saw Abu Kahil,andhe was a Companions, and my brother narrated to me that he said:'Isaw the Prophet (ﷺ) delivering the sermon atop his she-camel, andan Ethiopian was holding onto its reins.'" (RU)
English reference (RU): Vol. 1, Book 5, Hadith 1284 (RU)
Arabic reference (RU): Book 5, Hadith 1343 (RU)