Sunan an-Nasai Book 22, Hadith 2193

أَخْبَرَنَا زَكَرِيَّا بْنُ يَحْيَى، قَالَ أَنْبَأَنَا إِسْحَاقُ، قَالَ أَنْبَأَنَا عَبْدُ اللَّهِ بْنُ الْحَارِثِ، عَنْ يُونُسَ الأَيْلِيِّ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي عُرْوَةُ بْنُ الزُّبَيْرِ، أَنَّ عَائِشَةَ، أَخْبَرَتْهُ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم خَرَجَ فِي جَوْفِ اللَّيْلِ يُصَلِّي فِي الْمَسْجِدِ فَصَلَّى بِالنَّاسِ وَسَاقَ الْحَدِيثَ وَفِيهِ قَالَتْ فَكَانَ يُرَغِّبُهُمْ فِي قِيَامِ رَمَضَانَ مِنْ غَيْرِ أَنْ يَأْمُرَهُمْ بِعَزِيمَةٍ وَيَقُولُ ‏ "‏ مَنْ قَامَ لَيْلَةَ الْقَدْرِ إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ مَا تَقَدَّمَ مِنْ ذَنْبِهِ ‏"‏ ‏.‏ قَالَ فَتُوُفِّيَ رَسُولُ اللَّهِ صلى الله عليه وسلم وَالأَمْرُ عَلَى ذَلِكَ ‏.‏

It was narrated that Az-Zuhir said:"Urwah bin Az-Zubair told me that 'Aishah told him: 'The Messenger of Allah went out in the middle of the night to pray in the Masjid, and he led the people in prayer; and he quoted the same Hadith, in which she said: 'He used to encourage the people to pray Qiyam n Ramadan, without insisting on that.' He said: 'Whoever spends the night of Lailat Al-Qadr in prayer out of faith and in the hope of reward, he will be forgiven his previous sins.' He said: 'And the Messenger of Allah passed away when this was the state of affairs