Hadith
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
Sahih · Al-Albani
Sunan Abi Dawud 5160 ·Book 43, Hadith 388·Also available on sunnah.com·