Sahih Adab al-Mufrad

It is narrated from ‘Ubadah bin Walid bin ‘Ubadah bin Samit: My father and I set out, seeking knowledge among the Ansar before they passed away. The first person we met was Abu Yasar, a companion of the Prophet (ﷺ), and his slave was with him. Abu Yasar was wearing a striped Yemeni cloak and a Ma’afiri cloak, and his slave was also wearing a striped Yemeni cloak and a Ma’afiri cloak. I said to him: O uncle! If you took your slave’s cloak and gave him your Ma’afiri, or took his Ma’afiri and gave him your cloak, then both of you would have a matching set. He placed his hand on my head and said: O Allah! Bless him. O my nephew! These two eyes of mine have seen, these two ears of mine have heard, and my heart has well remembered—and he pointed to the middle of his chest—that the Prophet (ﷺ) used to say: Feed them from what you eat, and clothe them from what you wear. And if I give him worldly goods, it is easier for me than that he should take my good deeds on the Day of Resurrection.

Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) reports that the Prophet (peace and blessings of Allah be upon him) used to advise good treatment of slaves, and he would say: "Feed them from what you eat, and clothe them from what you wear. And do not punish the creation of Allah, the Mighty and Majestic."