Sahih al-Bukhari, Book 77, Hadith 73 (In-Book) ⓘ
Narrated Abu Huraira: Allah's Messenger said, "None of you should walk, wearing one shoe only; he should either put on both shoes or put on no shoes whatsoever."
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " لاَ يَمْشِي أَحَدُكُمْ فِي نَعْلٍ وَاحِدَةٍ لِيُحْفِهِمَا جَمِيعًا، أَوْ لِيَنْعَلْهُمَا جَمِيعًا " .
also referenced under: Hadith 5856 (DarusSalam) & Volume 7, Book 72, Hadith 746 (USC-MSA)