Sahih al-Bukhari 95:17
Narrated `Umar:
I came and behold, Allah's Messenger (ﷺ) was staying on a Mashroba (attic room) and a black slave of Allah's Messenger (ﷺ) was at the top if its stairs. I said to him, "(Tell the Prophet) that here is `Umar bin Al- Khattab (asking for permission to enter)." Then he admitted me.
Reference
Sahih al-Bukhari 95:17
In-book reference
Book 95, Hadith 17
Arabic Text
حَدَّثَنَا عَبْدُ الْعَزِيزِ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُلَيْمَانُ بْنُ بِلاَلٍ، عَنْ يَحْيَى، عَنْ عُبَيْدِ بْنِ حُنَيْنٍ، سَمِعَ ابْنَ عَبَّاسٍ، عَنْ عُمَرَ ـ رضى الله عنهم ـ قَالَ جِئْتُ فَإِذَا رَسُولُ اللَّهِ صلى الله عليه وسلم فِي مَشْرُبَةٍ لَهُ، وَغُلاَمٌ لِرَسُولِ اللَّهِ صلى الله عليه وسلم أَسْوَدُ عَلَى رَأْسِ الدَّرَجَةِ فَقُلْتُ قُلْ هَذَا عُمَرُ بْنُ الْخَطَّابِ فَأَذِنَ لِي.