حَدَّثَنَا عَفَّانُ حَدَّثَنَا حَاجِبُ بْنُ عُمَرَ أَبُو خُشَيْنَةَ أَخُو عِيسَى النَّحْوِيِّ قَالَ حَدَّثَنَا الْحَكَمُ بْنُ الْأَعْرَجِ قَالَ جَلَسْتُ إِلَى ابْنِ عَبَّاسٍ وَهُوَ مُتَوَسِّدٌ رِدَاءَهُ عِنْدَ بِئْرِ زَمْزَمَ فَجَلَسْتُ إِلَيْهِ وَكَانَ نِعْمَ الْجَلِيسُ فَسَأَلْتُهُ عَنْ عَاشُورَاءَ فَقَالَ عَنْ أَيِّ بَالِهِ تَسْأَلُ قُلْتُ عَنْ صِيَامِهِ قَالَ إِذَا رَأَيْتَ هِلَالَ الْمُحَرَّمِ فَاعْدُدْ فَإِذَا أَصْبَحْتَ مِنْ تَاسِعِهِ فَصُمْ ذَلِكَ الْيَوْمَ قُلْتُ أَهَكَذَا كَانَ يَصُومُهُ مُحَمَّدٌ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ نَعَمْ
مسند امام احمد بن حنبل · Hadith 2540
Al-Hakam bin al-A'raj said: I sat with Ibn 'Abbas (RA) when he was using his cloak as a pillow at the well of Zamzam. I sat with him, and what good company he was. I asked him about 'Ashoora' and he said: What about it? I said: Fasting it. He said: When you see the new moon of Muharram, count, and when it is the ninth day, fast that day. I said: Is this how Muhammad (PBUH) used to fast it? He said: Yes.
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020