Musnad Ahmad 46:1

'Abd al-Razzaq narrated to us, 'Umar ibn Hawshab narrated to us, Isma'il ibn Umayyah narrated to me, from his father, from his grandfather, who said: They had a servant boy called Tahman—or Dhakwan—and his grandfather emancipated half of him. The slave came to the Prophet, peace and blessings of Allah be upon him, and the Prophet, peace and blessings of Allah be upon him, said: "You are emancipated in your emancipation, and you are enslaved in your enslavement." He said: And he used to serve his master until he died. 'Abd al-Razzaq said: 'Umar—meaning Ibn Hawshab—was a righteous man. *** Yazid ibn Harun narrated to us, he said: 'Amir ibn Salih ibn Rustum al-Muzani informed us, Ayyub ibn Musa ibn 'Amr ibn Sa'id ibn al-'As narrated to us—he said: Or Ibn Sa'id ibn al-'As—from his father, from his grandfather, who said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "A father has not gifted his child anything better than good manners." 'Abd Allah ibn Ahmad said: Khalaf ibn Hisham al-Bazzar and al-Qawariri narrated it to us, they said: 'Amir ibn Abi 'Amir narrated to us with his chain of narration, and he mentioned the like of it.