Narrated Salama bin Al-Akwa`:

Allah's Messenger (ﷺ) said to a man from the tribe of Al-Aslam, "Proclaim among your people (or the people) on the day of 'Ashura' (tenth of Muharram), 'Whosoever has eaten anything should fast for the rest of the day; and whoever has not eaten anything, should complete his fast.' "

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى، عَنْ يَزِيدَ بْنِ أَبِي عُبَيْدٍ، حَدَّثَنَا سَلَمَةُ بْنُ الأَكْوَعِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ لِرَجُلٍ مِنْ أَسْلَمَ ‏

‏ أَذِّنْ فِي قَوْمِكَ ـ أَوْ فِي النَّاسِ ـ يَوْمَ عَاشُورَاءَ أَنَّ مَنْ أَكَلَ فَلْيُتِمَّ بَقِيَّةَ يَوْمِهِ، وَمَنْ لَمْ يَكُنْ أَكَلَ فَلْيَصُمْ ‏

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