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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
bukhari:4503 – Maḥmūd > ʿUbaydullāh > Isrāʾīl > Manṣūr > Ibrāhīm > ʿAlqamah > ʿAbdullāh

That Al-Ash'ath entered upon him while he was eating. Al-Ash'ath said, "Today is 'Ashura." I said (to him), "Fasting had been observed (on such a day) before (the order of compulsory fasting in) Ramadan was revealed. But when (the order of fasting in) Ramadan was revealed, fasting (on 'Ashura') was given up, so come and eat."  

البخاري:٤٥٠٣ – حَدَّثَنِي مَحْمُودٌ أَخْبَرَنَا عُبَيْدُ اللَّهِ عَنْ إِسْرَائِيلَ عَنْ مَنْصُورٍ عَنْ إِبْرَاهِيمَ عَنْ عَلْقَمَةَ عَنْ عَبْدِ اللَّهِ قَالَ دَخَلَ عَلَيْهِ الأَشْعَثُ وَهْوَ يَطْعَمُ فَقَالَ الْيَوْمُ عَاشُورَاءُ فَقَالَ كَانَ يُصَامُ قَبْلَ

أَنْ يَنْزِلَ رَمَضَانُ فَلَمَّا نَزَلَ رَمَضَانُ تُرِكَ فَادْنُ فَكُلْ  

See similar narrations below:

Collected by Nasāʾī's Kubrá
nasai-kubra:2858 – Muḥammad b. al-ʿAlāʾ > Abū Muʿāwiyah > al-Aʿmash > ʿUmārah b. ʿUmayr > ʿAbd al-Raḥman b. Yazīd

[Machine] "A day that the Messenger of Allah ﷺ used to fast before the arrival of Ramadan, but when Ramadan arrived, he abandoned it."  

الكبرى للنسائي:٢٨٥٨ – أَخْبَرَنَا مُحَمَّدُ بْنُ الْعَلَاءِ قَالَ حَدَّثَنَا أَبُو مُعَاوِيَةَ عَنِ الْأَعْمَشِ عَنْ عُمَارَةَ بْنِ عُمَيْرٍ عَنْ عَبْدِ الرَّحْمَنِ بْنِ يَزِيدَ قَالَ دَخَلَ الْأَشْعَثُ بْنُ قَيْسٍ عَلَى عَبْدِ اللهِ بْنِ مَسْعُودٍ يَوْمَ عَاشُورَاءَ وَهُوَ يَتَغَدَّى فَقَالَ لَهُ عَبْدُ اللهِ يَا أَبَا مُحَمَّدٍ ادْنُ قَالَ إِنِّي صَائِمٌ الْيَوْمَ يَوْمَ عَاشُورَاءَ قَالَ وَهَلْ تَدْرِي مَا كَانَ يَوْمُ عَاشُورَاءَ؟ قَالَ وَمَا كَانَ؟ قَالَ

«يَوْمٌ كَانَ يَصُومُهُ رَسُولُ اللهِ ﷺ قَبْلَ أَنْ يَنْزِلَ رَمَضَانُ فَلَمَّا نَزَلَ رَمَضَانُ تَرَكَهُ»