I came to Safwan bin Assal al-Muradi, and he asked, "What has brought you here?"I replied, "I am seeking knowledge."He said, "I heard the Messenger of Allah ﷺ say, 'No one leaves his home in pursuit of knowledge without the angels lowering their wings for him out of approval for what he is doing.'"
أتيت صفوان بن عسال المرادي فقال: ما جاء بك؟ قلت: أنبط العلم. قال: فإني سمعت رسول الله ﷺ يقول: ما من خارج خرج من بيته في طلب العلم إلا وضعت له الملائكة أجنحتها رضا بما يصنع.
Ibn Majah (226) narrated it via the route of Abdul-Razzaq, who said, Mamar reported to us, from Asim bin Abu Najud, from Zirr bin Hubaysh, and he mentioned it. Its chain is hasan because of Asim bin Abu Najud, for he is hasan al-hadith. Ibn Khuzayma (193) and Ibn Hibban (1319) graded it sahih, and both narrated it from this same route. Darimi (369) also narrated it via the route of Hammad bin Salama, from Asim, with it, as a raised (marfu) narration.It does no harm that Tirmidhi (3535), Nasai (158), Ibn Khuzayma (17), and Ibn Hibban (1100), all of them via the route of Sufyan, from Asim, with his chain, narrated it as a stopped (mawquf) narration, because whoever narrated it as marfu has additional knowledge with him. Tirmidhi (3536) also narrated it from another route from Asim, and in it, "It has reached me that the angels lower their wings," then he mentioned the hadith. This indicates that it reached him from the Prophet ﷺ, or, at the very least, from one of the companions.Ibn Abdul-Barr narrated it in Jami Bayan Ilm (162) via the route of Arim bin Fadl, from Saqa bin Hazn, from Ali bin Hakam, from Minhal bin Amr, from Zirr bin Hubaysh, who said, a man from Murad called Safwan bin Assal came to the Messenger of Allah ﷺ while he was in the masjid, leaning on a red cloak of his, and said, "O Messenger of Allah, I have come seeking knowledge..." He said, "Welcome to the seeker of knowledge, for the angels surround the seeker of knowledge and shade him with their wings, mounting one upon another, until they rise to the lowest heaven, out of love for what he seeks. So what have you come seeking?" He said, "O Messenger of Allah, I keep traveling between Makkah and Madinah, so give me a ruling about wiping over the leather socks..." then he mentioned the hadith.Tabarani (7347) narrated it via the route of Shayban bin Farroukh, from Saqa bin Hazn, with it, except that he inserted Abdullah bin Masud between Safwan bin Assal and Zirr. It appears that this is a mistake on the part of Shayban, for he is truthful but prone to error.Ibn Abdul-Barr said in Jami Bayan Ilm (159/1), "This hadith of Safwan bin Assal was narrated as stopped (mawquf) by a group from Asim, while others narrated it from him as raised (marfu), and it is a sahih, hasan, firmly established, well preserved, marfu hadith, and the like of it cannot be said based on personal opinion..." then he listed some of the sahih routes by which the hadith was transmitted as stopped (mawquf) on Safwan bin Assal.His statement, "I extract knowledge," comes from the root meaning to bring something out or draw it forth, that is, to extract it. What is meant is, I seek knowledge. And in some narrations of the hadith it reads, "So I said, seeking knowledge."