صحيح ابن خزيمه
Sahih Ibn Khuzaymah
Hadith Number: 2080
حدثنا محمد بن بشار , حدثنا يحيى , عن هشام , عن ابيه , عن عائشة ، انها قالت:" كان يوم عاشوراء يوما تصومه قريش في الجاهلية , وكان رسول الله صلى الله عليه وسلم يصومه , فلما قدم يعني المدينة صامه , وامر بصيامه , فلما نزل رمضان، فكان رمضان هو الفريضة وترك عاشوراء , فكان من شاء صامه , ومن شاء لم يصمه"
Lady Aisha (may Allah be pleased with her) narrates that the Quraish used to fast on the day of Ashura during the days of ignorance, and the Messenger of Allah (peace be upon him) also used to fast on this day. Then when he migrated to Madinah, he (peace be upon him) fasted on this day and ordered his companions to fast as well. Then, when the fasting of Ramadan was made obligatory, only the fasting of Ramadan remained obligatory and the fasting of Ashura was abandoned. Therefore, whoever wished would fast on this day, and whoever wished would not fast.
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