Sahih Bukhari Volume 3, Book 49, Hadith 2531

حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ، عَنْ مُحَمَّدِ بْنِ بِشْرٍ، عَنْ إِسْمَاعِيلَ، عَنْ قَيْسٍ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ أَنَّهُ لَمَّا أَقْبَلَ يُرِيدُ الإِسْلاَمَ وَمَعَهُ غُلاَمُهُ، ضَلَّ كُلُّ وَاحِدٍ مِنْهُمَا مِنْ صَاحِبِهِ، فَأَقْبَلَ بَعْدَ ذَلِكَ وَأَبُو هُرَيْرَةَ جَالِسٌ مَعَ النَّبِيِّ صلى الله عليه وسلم فَقَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ يَا أَبَا هُرَيْرَةَ، هَذَا غُلاَمُكَ قَدْ أَتَاكَ ‏"‏‏.‏ فَقَالَ أَمَا إِنِّي أُشْهِدُكَ أَنَّهُ حُرٌّ‏.‏ قَالَ فَهُوَ حِينَ يَقُولُ يَا لَيْلَةً مِنْ طُولِهَا وَعَنَائِهَا عَلَى أَنَّهَا مِنْ دَارَةِ الْكُفْرِ نَجَّتِ

Narrated By Qais : When Abu Huraira accompanied by his slave set out intending to embrace Islam they lost each other on the way. The slave then came while Abu Huraira was sitting with the Prophet. The Prophet said, "O Abu Huraira! Your slave has come back." Abu Huraira said, "Indeed, I would like you to witness that I have manumitted him." That happened at the time when Abu Huraira recited (the following poetic verse): 'What a long tedious tiresome night! Nevertheless, it has delivered us From the land of Kufr (disbelief).