حَدَّثَنِي عَمْرٌو النَّاقِدُ، حَدَّثَنَا سُفْيَانُ، عَنِ الزُّهْرِيِّ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، - رضى الله عنها - أَنَّ يَوْمَ، عَاشُورَاءَ كَانَ يُصَامُ فِي الْجَاهِلِيَّةِ فَلَمَّا جَاءَ الإِسْلاَمُ مَنْ شَاءَ صَامَهُ وَمَنْ شَاءَ تَرَكَهُ ‏.‏

'A'isha (Allah be pleased with her) reported. In the pre-Islamic days fast was observed on the day of Ashura, but with the advent of Islam (its position was ascertained as that of a voluntary fast). Then he who wished to fast fasted, and he who liked to abandon it abandoned it. Translation Not Available

Book Ref: Sahih Muslim Book 13 Hadith 2501
Web Ref:  Sahih Muslim Book 6 Hadith 1125 c

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