Manumission of Slaves
حَدَّثَنَا إِسْحَاقُ بْنُ نَصْرٍ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنِ الأَعْمَشِ، حَدَّثَنَا أَبُو صَالِحٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم " نِعْمَ مَا لأَحَدِهِمْ يُحْسِنُ عِبَادَةَ رَبِّهِ وَيَنْصَحُ لِسَيِّدِهِ ".Narrated Abu Huraira:The Prophet (ﷺ) said, "Goodness and comfort are for him who worships his Lord in a perfect manner and serves his master sincerely
From Sahih al-Bukhari, whose reports the scholars accept as authentic.