Sahih Muslim , Book 4, Hadith 843 (USC-MSA) ⓘ
Anas reported: The Apostle of Allah did not come to us for three days. When the prayer was about to start. Abu Bakr stepped forward (to lead the prayer), and the Messenger of Allah lifted the curtain. When the face of the Messenger of Allah became visible to us, we (found) that no sight was more endearing to us than the face of the Messenger of Allah as it appeared to us. The Apostle of Allah with the gesture of his hand directed Abu Bakr to step forward (and lead the prayer). The Apostle of Allah then drew the curtain, and we could not see him till he died.
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَهَارُونُ بْنُ عَبْدِ اللَّهِ، قَالاَ حَدَّثَنَا عَبْدُ الصَّمَدِ، قَالَ سَمِعْتُ أَبِي يُحَدِّثُ، قَالَ حَدَّثَنَا عَبْدُ الْعَزِيزِ، عَنْ أَنَسٍ، قَالَ لَمْ يَخْرُجْ إِلَيْنَا نَبِيُّ اللَّهِ صلى الله عليه وسلم ثَلاَثًا فَأُقِيمَتِ الصَّلاَةُ فَذَهَبَ أَبُو بَكْرٍ يَتَقَدَّمُ فَقَالَ نَبِيُّ اللَّهِ صلى الله عليه وسلم بِالْحِجَابِ فَرَفَعَهُ فَلَمَّا وَضَحَ لَنَا وَجْهُ نَبِيِّ اللَّهِ صلى الله عليه وسلم مَا نَظَرْنَا مَنْظَرًا قَطُّ كَانَ أَعْجَبَ إِلَيْنَا مِنْ وَجْهِ النَّبِيِّ صلى الله عليه وسلم حِينَ وَضَحَ لَنَا - قَالَ - فَأَوْمَأَ نَبِيُّ اللَّهِ صلى الله عليه وسلم بِيَدِهِ إِلَى أَبِي بَكْرٍ أَنْ يَتَقَدَّمَ وَأَرْخَى نَبِيُّ اللَّهِ صلى الله عليه وسلم الْحِجَابَ فَلَمْ نَقْدِرْ عَلَيْهِ حَتَّى مَاتَ .
also referenced under: Book 4, Hadith 109 (In-Book) & Hadith 419 (Reference)