The Eyewitness Account of `Uthman [ibn Maz'un] of Revelation and his Conversion to Islam because of it.
Ash-Sha`bi reported that Shatiyr bin Shakl said: "I heard Ibn Mas`ud say: `The most comprehensive Ayah in the Qur'an is in Surat An-Nahl:
[إِنَّ اللَّهَ يَأْمُرُ بِالْعَدْلِ وَالإْحْسَانِ]
(Verily, Allah enjoins justice and kindness...) [Qur'an Al Nahl 16:90]
It was reported by Ibn Jarir.
Concerning the revelation of this Ayah, Imam Ahmad reported a Hasan [good] Hadith from `Abdullah bin `Abbas who said:
"While the Messenger of Allah was sitting in the courtyard of his house, `Uthman bin Maz`un passed by and smiled at the Messenger of Allah . The Messenger of Allah said to him,
«أَلَا تَجْلِسُ؟»
(Won't you sit down) He said, `Certainly.' So the Messenger of Allah sat facing him, and while they were talking, the Messenger of Allah began looking up at the sky, looking at it for a while, then he brought his gaze down until he was looking at the ground to his right. Then the Messenger of Allah turned slightly away from his companion `Uthman to where he was looking. Then he began to tilt his head as if trying to understand something, and Ibn Maz`un was looking on.
When the matter was finished and he had understood what had been said to him, the Messenger of Allah stared at the sky again as he had the first time, looking at whatever he could see until it disappeared. Then he turned back to face `Uthman again.
`Uthman said, `O Muhammad, I have never seen you do anything like you did today while I was sitting with you.' The Messenger of Allah said:
«وَمَا رَأَيْتَنِي فَعَلْتُ؟»
(What did you see me do) `Uthman said: `I saw you staring at the sky, then you lowered your gaze until you were looking to your right, then you turned to him and left me. Then you tilted your head as if you were trying to understand something that was being said to you.' The Messenger of Allah said,
«وَفَطِنْتَ لِذَلِكَ؟»
(Did you notice that) `Uthman said, `Yes'. The Messenger of Allah said:
«أَتَانِي رَسُولُ اللهِ آنِفًا وَأَنْتَ جَالِس»
(A messenger from Allah came to me just now, when you were sitting here.) `Uthman said, `A messenger from Allah' The Messenger of Allah said,
«نَعَم»
(Yes.) `Uthman said, `And what did he say to you' The Messenger of Allah said:
[إِنَّ اللَّهَ يَأْمُرُ بِالْعَدْلِ وَالإْحْسَانِ]
(Verily, Allah orders justice and kindness...)
`Uthman said: `That was when faith was established in my heart and I began to love Muhammad .''
It is a Hasan Hadith having a good connected chain of narrators in which their hearing it from each other is clear.
Tafsir ibn Kathir - Surah Nahl;
http://www.tafsir.com/default.asp?sid=16&tid=28127
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