Sunan Ibn Majah, Book 1, Hadith 231 (In-Book) ⓘ
It was narrated that Zirr bin Hubaish said: "I went to Safwan bin 'Assal Al-Muradi and he said: 'What brought you here?' I said: 'I am seeking knowledge.' He said: 'I heard the Messenger of Allah say: "There is no one who goes out of his house in order to seek knowledge, but the angels lower their wings in approval of his action.'"
حَدَّثَنَا مُحَمَّدُ بْنُ يَحْيَى، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَنْبَأَنَا مَعْمَرٌ، عَنْ عَاصِمِ بْنِ أَبِي النَّجُودِ، عَنْ زِرِّ بْنِ حُبَيْشٍ، قَالَ أَتَيْتُ صَفْوَانَ بْنَ عَسَّالٍ الْمُرَادِيَّ فَقَالَ مَا جَاءَ بِكَ قُلْتُ أُنْبِطُ الْعِلْمَ . قَالَ فَإِنِّي سَمِعْتُ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ يَقُولُ " مَا مِنْ خَارِجٍ خَرَجَ مِنْ بَيْتِهِ فِي طَلَبِ الْعِلْمِ إِلاَّ وَضَعَتْ لَهُ الْمَلاَئِكَةُ أَجْنِحَتَهَا رِضًا بِمَا يَصْنَعُ " .
also referenced under: Hadith 226 (Reference) & Volume 1, Book 1, Hadith 226 (DarusSalam)