Muwatta Malik, Book 9, Hadith 74 (USC-MSA)

Yahya related to me from Malik from Nafi from Abdullah ibn Umar that when the Messenger of Allah, may Allah bless him and grant him peace, used to go to Quba (to pray), he would walk as well as ride.

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَأْتِي قُبَاءً رَاكِبًا وَمَاشِيًا ‏.‏

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also referenced under: Book 9, Hadith 405 (In-Book)