Sahih Muslim , Book 6, Hadith 2631 (USC-MSA) ⓘ
'Abdullah b. Unais reported Allah's Messenger as saying: I was shown Lailat-ul-Qadr; then I was made to forget it, and saw that I was prostrating in water and clay in the morning of that (night). He (the narrator) said: There was a downpour on the twenty-third night and the Messenger of Allah led us in prayer, and as he went back, there was a trace of water and clay on his forehead and on his nose. He (the narrator) said: 'Abdullah b. Unais used to say that it was the twenty-third (night).
وَحَدَّثَنَا سَعِيدُ بْنُ عَمْرِو بْنِ سَهْلِ بْنِ إِسْحَاقَ بْنِ مُحَمَّدِ بْنِ الأَشْعَثِ بْنِ قَيْسٍ، الْكِنْدِيُّ وَعَلِيُّ بْنُ خَشْرَمٍ قَالاَ حَدَّثَنَا أَبُو ضَمْرَةَ، حَدَّثَنِي الضَّحَّاكُ بْنُ عُثْمَانَ، - وَقَالَ ابْنُ خَشْرَمٍ عَنِ الضَّحَّاكِ بْنِ عُثْمَانَ، - عَنْ أَبِي النَّضْرِ، مَوْلَى عُمَرَ بْنِ عُبَيْدِ اللَّهِ عَنْ بُسْرِ بْنِ، سَعِيدٍ عَنْ عَبْدِ اللَّهِ بْنِ أُنَيْسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " أُرِيتُ لَيْلَةَ الْقَدْرِ ثُمَّ أُنْسِيتُهَا وَأَرَانِي صُبْحَهَا أَسْجُدُ فِي مَاءٍ وَطِينٍ " . قَالَ فَمُطِرْنَا لَيْلَةَ ثَلاَثٍ وَعِشْرِينَ فَصَلَّى بِنَا رَسُولُ اللَّهِ صلى الله عليه وسلم فَانْصَرَفَ وَإِنَّ أَثَرَ الْمَاءِ وَالطِّينِ عَلَى جَبْهَتِهِ وَأَنْفِهِ . قَالَ وَكَانَ عَبْدُ اللَّهِ بْنُ أُنَيْسٍ يَقُولُ ثَلاَثٍ وَعِشْرِينَ .
also referenced under: Book 13, Hadith 281 (In-Book) & Hadith 1168 (Reference)