Sunan Abi Dawud, Hadith 2502

Anas bin Malik reported on the authority of his father, The Apostle of Allaah said “ You left behind some people in Madeenah who did not fail to be with you wherever you went and whatever you spent (of your goods) and whatever valley you crossed. They asked Apostle of Allaah how can they be with us when they are still in Madeenah? He replied “They were declined by a valid excuse.”

حَدَّثَنَا مُوسَى بْنُ إِسْمَاعِيلَ، حَدَّثَنَا حَمَّادٌ، عَنْ حُمَيْدٍ، عَنْ مُوسَى بْنِ أَنَسِ بْنِ مَالِكٍ، عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏:‏ ‏"‏ لَقَدْ تَرَكْتُمْ بِالْمَدِينَةِ أَقْوَامًا مَا سِرْتُمْ مَسِيرًا وَلاَ أَنْفَقْتُمْ مِنْ نَفَقَةٍ وَلاَ قَطَعْتُمْ مِنْ وَادٍ إِلاَّ وَهُمْ مَعَكُمْ فِيهِ ‏"‏ ‏.‏ قَالُوا ‏:‏ يَا رَسُولَ اللَّهِ وَكَيْفَ يَكُونُونَ مَعَنَا وَهُمْ بِالْمَدِينَةِ فَقَالَ ‏:‏ ‏"‏ حَبَسَهُمُ الْعُذْرُ ‏"‏ ‏.‏

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also referenced under: Hadith 2508 (DarusSalam)