(8) باب صُحْبَةِ الْمَمَالِيكِ وَكَفَّارَةِ مَنْ لَطَمَ عَبْدَهُ
Hilal b. Yasaf reported that a person got angry and slapped his slave-girl. Thereupon Suwaid b. Muqarrin said to him:
You could find no other part (to slap) but the prominent part of her face. See I was one of the seven sons of Muqarrin, and we had but only one slave-girl. The youngest of us slapped her, and Allah's Messenger (ﷺ) commanded us to set her free. 2097
Reference: Sahih Muslim 1658 b
In-book reference: Book 27, Hadith 50
USC-MSA web (English) reference(deprecated numbering scheme): Book 15, Hadith 4082