Sunan Abi Dawud 654
سنن أبي داود#654Sahihحَدَّثَنَا الْحَسَنُ بْنُ عَلِيٍّ، حَدَّثَنَا عُثْمَانُ بْنُ عُمَرَ، حَدَّثَنَا صَالِحُ بْنُ رُسْتُمَ أَبُو عَامِرٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ قَيْسٍ، عَنْ يُوسُفَ بْنِ مَاهَكَ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا صَلَّى أَحَدُكُمْ فَلاَ يَضَعْ نَعْلَيْهِ عَنْ يَمِينِهِ وَلاَ عَنْ يَسَارِهِ فَتَكُونَ عَنْ يَمِينِ غَيْرِهِ إِلاَّ أَنْ لاَ يَكُونَ عَنْ يَسَارِهِ أَحَدٌ وَلْيَضَعْهُمَا بَيْنَ رِجْلَيْهِ " .
Narrated AbuHurayrah: The Prophet (ﷺ) said: When any of you prays, he should not place his sandals on his right side or on his left so as to be on the right side of someone else, unless no one is at his left, but should place them between his feet
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 2:264