Sahih Bukhari Volume 1, Book 10, Hadith 681

حَدَّثَنَا أَبُو مَعْمَرٍ، قَالَ حَدَّثَنَا عَبْدُ الْوَارِثِ، قَالَ حَدَّثَنَا عَبْدُ الْعَزِيزِ، عَنْ أَنَسٍ، قَالَ لَمْ يَخْرُجِ النَّبِيُّ صلى الله عليه وسلم ثَلاَثًا، فَأُقِيمَتِ الصَّلاَةُ، فَذَهَبَ أَبُو بَكْرٍ يَتَقَدَّمُ فَقَالَ نَبِيُّ اللَّهِ صلى الله عليه وسلم بِالْحِجَابِ فَرَفَعَهُ، فَلَمَّا وَضَحَ وَجْهُ النَّبِيِّ صلى الله عليه وسلم مَا نَظَرْنَا مَنْظَرًا كَانَ أَعْجَبَ إِلَيْنَا مِنْ وَجْهِ النَّبِيِّ صلى الله عليه وسلم حِينَ وَضَحَ لَنَا، فَأَوْمَأَ النَّبِيُّ صلى الله عليه وسلم بِيَدِهِ إِلَى أَبِي بَكْرٍ أَنْ يَتَقَدَّمَ، وَأَرْخَى النَّبِيُّ صلى الله عليه وسلم الْحِجَابَ، فَلَمْ يُقْدَرْ عَلَيْهِ حَتَّى مَاتَ‏

Narrated By Anas : The Prophet did not come out for three days. The people stood for the prayer and Abu Bakr went ahead to lead the prayer. (In the meantime) the Prophet caught hold of the curtain and lifted it. When the face of the Prophet appeared we had never seen a scene more pleasing than the face of the Prophet as it appeared then. The Prophet beckoned to Abu Bakr to lead the people in the prayer and then let the curtain fall. We did not see him (again) till he died.