حَدَّثَنَا مُعَاذُ بْنُ مُعَاذٍ حَدَّثَنَا حَاجِبُ بْنُ عُمَرَ حَدَّثَنِي عَمِّي الْحَكَمُ بْنُ الْأَعْرَجِ قَالَ أَتَيْتُ ابْنَ عَبَّاسٍ وَهُوَ مُتَّكِئٌ عِنْدَ زَمْزَمَ فَجَلَسْتُ إِلَيْهِ وَكَانَ نِعْمَ الْجَلِيسُ فَقُلْتُ أَخْبِرْنِي عَنْ يَوْمِ عَاشُورَاءَ قَالَ عَنْ أَيِّ بَالِهِ تَسْأَلُ قُلْتُ عَنْ صَوْمِهِ قَالَ إِذَا رَأَيْتَ هِلَالَ الْمُحَرَّمِ فَاعْدُدْ فَإِذَا أَصْبَحْتَ مِنْ تَاسِعَةٍ فَأَصْبِحْ مِنْهَا صَائِمًا قُلْتُ أَكَذَاكَ كَانَ يَصُومُهُ مُحَمَّدٌ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ نَعَمْ
مسند امام احمد بن حنبل · Hadith 2135
Hajib bin 'Umar narrated: My paternal uncle al-Hakam bin al-A'raj told me: I came to Ibn 'Abbas (RA) when he was reclining beside Zamzam, and I sat with him and what good company he was. I said: Tell me about the day of 'Ashoora.' He said: What do you want to know about it? I said: About fasting it; on what day should I fast? He said: When you see the new moon of Muharram, then count, and on the ninth day, fast that day. I said: Is that 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