General Behavior (Kitab Al-Adab)
43/134. Chapter:
Regarding the rights of slaves
Sunan Abi Dawud
حَدَّثَنَا أَبُو كَامِلٍ، حَدَّثَنَا عَبْدُ الْوَاحِدِ، عَنِ الأَعْمَشِ، بِإِسْنَادِهِ وَمَعْنَاهُ نَحْوَهُ قَالَ كُنْتُ أَضْرِبُ غُلاَمًا لِي أَسْوَدَ بِالسَّوْطِ وَلَمْ يَذْكُرْ أَمْرَ الْعِتْقِ .
The tradition mentioned above has also been transmitted by al-A’mash in a similar way to same way to the same effect through a different chain of narrators.
Reference : Sunan Abi Dawud 5160In-book reference : Book 43, Hadith 388English translation : Book 42, Hadith 5141