Some men amongst the companions of the Prophet ﷺ were shown in their dreams that the night of Qadr was in the last seven nights of Ramadan. Messenger of Allah ﷺ said, "It seems that all your dreams agree that (the Night of Qadr) is in the last seven nights, and whoever wants to search for it (i.e. the Night of Qadr) should search in the last seven (nights of Ramadan).

أَنَّ رِجَالاً مِنْ أَصْحَابِ النَّبِيِّ ﷺ أُرُوا لَيْلَةَ الْقَدْرِ فِي الْمَنَامِ فِي السَّبْعِ الأَوَاخِرِ فَقَالَ رَسُولُ اللَّهِ ﷺ أَرَى رُؤْيَاكُمْ قَدْ تَوَاطَأَتْ فِي السَّبْعِ الأَوَاخِرِ فَمَنْ كَانَ مُتَحَرِّيَهَا فَلْيَتَحَرَّهَا فِي السَّبْعِ الأَوَاخِرِ

I asked Abu Saʿid, and he was a friend of mine, (about the Night of Qadr) and he said, "We practiced Iʿtikaf (seclusion in the mosque) in the middle third of the month of Ramadan with the Prophet ﷺ . In the morning of the 20th of Ramadan, the Prophet ﷺ came and addressed us and said, 'I was informed of (the date of the Night of Qadr) but I was caused to forget it; so search for it in the odd nights of the last ten nights of the month of Ramadan. (In the dream) I saw myself prostrating in mud and water (as a sign). So, whoever was in Iʿtikaf with me should return to it with me (for another 10-day's period)', and we returned. At that time there was no sign of clouds in the sky but suddenly a cloud came and it rained till rainwater started leaking through the roof of the mosque which was made of date-palm leaf stalks. Then the prayer was established and I saw Messenger of Allah ﷺ prostrating in mud and water and I saw the traces of mud on his forehead."

سَأَلْتُ أَبَا سَعِيدٍ وَكَانَ لِي صَدِيقًا فَقَالَ اعْتَكَفْنَا مَعَ النَّبِيِّ ﷺ الْعَشْرَ الأَوْسَطَ مِنْ رَمَضَانَ فَخَرَجَ صَبِيحَةَ عِشْرِينَ فَخَطَبَنَا وَقَالَ إِنِّي أُرِيتُ لَيْلَةَ الْقَدْرِ ثُمَّ أُنْسِيتُهَا أَوْ نُسِّيتُهَا فَالْتَمِسُوهَا فِي الْعَشْرِ الأَوَاخِرِ فِي الْوَتْرِ وَإِنِّي رَأَيْتُ أَنِّي أَسْجُدُ فِي مَاءٍ وَطِينٍ فَمَنْ كَانَ اعْتَكَفَ مَعَ رَسُولِ اللَّهِ ﷺ فَلْيَرْجِعْ فَرَجَعْنَا وَمَا نَرَى فِي السَّمَاءِ قَزَعَةً فَجَاءَتْ سَحَابَةٌ فَمَطَرَتْ حَتَّى سَالَ سَقْفُ الْمَسْجِدِ وَكَانَ مِنْ جَرِيدِ النَّخْلِ وَأُقِيمَتِ الصَّلاَةُ فَرَأَيْتُ رَسُولَ اللَّهِ ﷺ يَسْجُدُ فِي الْمَاءِ وَالطِّينِ حَتَّى رَأَيْتُ أَثَرَ الطِّينِ فِي جَبْهَتِهِ

The Messenger of Allah ﷺ used to observe i'tikaf in Ramadan during the ten nights in the middle of the month. When evening came after twenty nights had passed and the twenty-first was beginning, he would return to his dwelling, and those who had been observing i'tikaf with him would return as well.

Then, in a month in which he was observing i'tikaf, he remained on the night on which he used to return. He addressed the people and instructed them as Allah willed, then said: "I used to observe i'tikaf during these ten, but it has now become apparent to me that I should observe i'tikaf during these last ten. So whoever was observing i'tikaf with me should remain in his place of i'tikaf. I was shown this night, then I was made to forget it, so seek it in the last ten, and seek it on every odd night. I saw myself prostrating in water and mud."

The sky then opened up with rain on that night, and it rained, so the mosque leaked at the prayer place of the Prophet ﷺ on the night of the twenty-first. My own eyes saw the Messenger of Allah ﷺ, and I looked at him as he left from the morning prayer with his face full of mud and water.

كَانَ رَسُولُ اللَّهِ ﷺ يُجَاوِرُ فِي رَمَضَانَ الْعَشْرَ الَّتِي فِي وَسَطِ الشَّهْرِ، فَإِذَا كَانَ حِينَ يُمْسِي مِنْ عِشْرِينَ لَيْلَةً تَمْضِي وَيَسْتَقْبِلُ إِحْدَى وَعِشْرِينَ رَجَعَ إِلَى مَسْكَنِهِ، وَرَجَعَ مَنْ كَانَ يُجَاوِرُ مَعَهُ.

وَأَنَّهُ أَقَامَ فِي شَهْرٍ جَاوَرَ فِيهِ اللَّيْلَةَ الَّتِي كَانَ يَرْجِعُ فِيهَا، فَخَطَبَ النَّاسَ، فَأَمَرَهُمْ مَا شَاءَ اللَّهُ، ثُمَّ قَالَ: «كُنْتُ أُجَاوِرُ هَذِهِ الْعَشْرَ، ثُمَّ قَدْ بَدَا لِي أَنْ أُجَاوِرَ هَذِهِ الْعَشْرَ الأَوَاخِرَ، فَمَنْ كَانَ اعْتَكَفَ مَعِي فَلْيَثْبُتْ فِي مُعْتَكَفِهِ، وَقَدْ أُرِيتُ هَذِهِ اللَّيْلَةَ ثُمَّ أُنْسِيتُهَا، فَابْتَغُوهَا فِي الْعَشْرِ الأَوَاخِرِ، وَابْتَغُوهَا فِي كُلِّ وِتْرٍ، وَقَدْ رَأَيْتُنِي أَسْجُدُ فِي مَاءٍ وَطِينٍ».

فَاسْتَهَلَّتِ السَّمَاءُ فِي تِلْكَ اللَّيْلَةِ فَأَمْطَرَتْ، فَوَكَفَ الْمَسْجِدُ فِي مُصَلَّى النَّبِيِّ ﷺ لَيْلَةَ إِحْدَى وَعِشْرِينَ، فَبَصُرَتْ عَيْنِي رَسُولَ اللَّهِ ﷺ، وَنَظَرْتُ إِلَيْهِ انْصَرَفَ مِنَ الصُّبْحِ وَوَجْهُهُ مُمْتَلِئٌ طِينًا وَمَاءً.

Messenger of Allah ﷺ used to practice Iʿtikaf in the last ten nights of Ramadan and used to say, "Look for the Night of Qadr in the last ten nights of the month of Ramadan."

كَانَ رَسُولُ اللَّهِ ﷺ يُجَاوِرُ فِي الْعَشْرِ الأَوَاخِرِ مِنْ رَمَضَانَ وَيَقُولُ تَحَرَّوْا لَيْلَةَ الْقَدْرِ فِي الْعَشْرِ الأَوَاخِرِ مِنْ رَمَضَانَ