Sunan Ibn Majah, Chapter: The Chapters on Blood Money

from his father that his grandfather said: "A man came to the Prophet (saw) screaming. The Messenger of Allah (saw) said to him: 'What is the matter with you?' He said: 'My master saw me kissing a slave woman of his, so he cut off my penis.' The Prophet (saw) said: 'Take me to the man.' He was sought but could not be found, so the Messenger of Allah (saw) said: 'Go, for you are free.' He said: 'Who will protect me, O Messenger of Allah (saw)? What if my master enslaves me again?' The Messenger of Allah (saw) said: 'Your protection will be (incumbent upon) every believer or Muslim.'" Hasan