The virtue of Lailat Al-Qadr and the Exhortation to seek it; When it is and the most likely times to seek it Sahih Muslim 1165 a
Arabic hadith text
وَحَدَّثَنَا يَحْيَى بْنُ يَحْيَى، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، - رضى الله عنهما - أَنَّ رِجَالاً، مِنْ أَصْحَابِ النَّبِيِّ صلى الله عليه وسلم أُرُوا لَيْلَةَ الْقَدْرِ فِي الْمَنَامِ فِي السَّبْعِ الأَوَاخِرِ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم "أَرَى رُؤْيَاكُمْ قَدْ تَوَاطَأَتْ فِي السَّبْعِ الأَوَاخِرِ فَمَنْ كَانَ مُتَحَرِّيَهَا فَلْيَتَحَرَّهَا فِي السَّبْعِ الأَوَاخِرِ "
Translation
Ibn 'Umar (Allah be pleased with them) reported that some persons among the Companions of the Messenger of Allah (ﷺ) were shown Lailat- ul-Qadr while sleeping in the last week (of Ramadan). Thereupon Allah's Messenger (ﷺ) said
I see that your dreams agree regarding the last week; so he who wants to seek it should seek it in the last week (during the night).