Sahih Muslim — The Book of Prayer - Travellers — Hadith No: 1782
حَدَّثَنِي مُحَمَّدُ بْنُ رَافِعٍ، حَدَّثَنَا شَبَابَةُ، حَدَّثَنِي وَرْقَاءُ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " مَنْ يَقُمْ لَيْلَةَ الْقَدْرِ فَيُوَافِقُهَا - أُرَاهُ قَالَ - إِيمَانًا وَاحْتِسَابًا غُفِرَ لَهُ " .
Translation
Abu Huraira reported Allah's Apostle (ﷺ) as saying:He who prayed on the Lailat-ul-Qadr (the Majestic Night) knowing that it is (the same night). I (believe) that he (the Prophet also) said: (He who does) it with faith and seeking reward (from Allah), his sins would be forgiven