Narrated Abu Burdah:On the authority of his father: The Messenger of Allah (ﷺ) commanded us to proceed to the land of Negus. Mentioning the rest of the tradition he said that Negus said: I bear witness that he is the Messenger of Allah (ﷺ), and it is he about whom Christ son of Mary gave good news. It I were not in the land which I am, I would come to him and carry his shoes

English translation · Sunan Abu Dawud