Al-Bara’ ibn ‘Azib reported: A man was reciting Surat al-Kahf and in his barn was a animal which became unsettled. As he looked, there was a mist or a cloud overshadowing him. He mentioned that to the Prophet, peace and blessings be upon him, and he said, “Continue reciting, for it was calm which descended with the Quran, or for the Quran.”
Source: Ṣaḥīḥ al-Bukhārī 3614, Ṣaḥīḥ Muslim 795
Grade: Muttafaqun Alayhi (authenticity agreed upon) according to Al-Bukhari and Muslim
عن البراء بن عازب قال قَرَأَ رَجُلٌ الْكَهْفَ وَفِي الدَّارِ دَابَّةٌ فَجَعَلَتْ تَنْفِرُ فَنَظَرَ فَإِذَا ضَبَابَةٌ أَوْ سَحَابَةٌ قَدْ غَشِيَتْهُ قَالَ فَذَكَرَ ذَلِكَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ اقْرَأْ فُلَانُ فَإِنَّهَا السَّكِينَةُ تَنَزَّلَتْ عِنْدَ الْقُرْآنِ أَوْ تَنَزَّلَتْ لِلْقُرْآنِ
3614 صحيح البخاري كتاب المناقب باب علامات النبوة في الإسلام
795 صحيح مسلم كتاب صلاة المسافرين وقصرها باب نزول السكينة لقراءة القرآن