Full Sharh — Al-Adab Al-Mufrad 159
حَدَّثَنَا عَبْدُ اللهِ بْنُ صَالِحٍ قَالَ: حَدَّثَنِي مُعَاوِيَةُ بْنُ صَالِحٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ جُبَيْرِ بْنِ نُفَيْرٍ، عَنْ أَبِيهِ، عَنْ أَبِي الدَّرْدَاءِ، أَنَّهُ كَانَ يَقُولُ لِلنَّاسِ: نَحْنُ أَعْرَفُ بِكُمْ مِنَ الْبَيَاطِرَةِ بِالدَّوَابِّ، قَدْ عَرَفْنَا خِيَارَكُمْ مِنْ شِرَارِكُمْ. أَمَّا خِيَارُكُمُ: الَّذِي يُرْجَى خَيْرُهُ، وَيُؤْمَنُ شَرُّهُ. وَأَمَّا شِرَارُكُمْ: فَالَّذِي لاَ يُرْجَى خَيْرُهُ، وَلاَ يُؤْمَنُ شَرُّهُ، وَلاَ يُعْتَقُ مُحَرَّرُهُ.
English Translation
Abu'd-Darda' used to say to people. "We know you better than the veterinarian knows his animals. We recognise the best of you from the worst of you. The best of you is the one whose good is hoped for and the one whose evil you are safe from. As for the worst of you, that is the person whose good is not hoped for and whose evil you are not safe from and he does not free slaves."
Source
Al-Adab Al-Mufrad(الأدب المفرد)
Being a master
Hadith Number
159