Sahih Muslim , Hadith 1133 ⓘ
Hakam b. al-'Araj reported: I went to Ibn 'Abbas (Allah be Pleased with both of them) and he was reclining using his mantle as a pillow near the fountain of Zamzam. I said to him: Tell me about fasting on Ashura. He said: When you see the new moon of Muharram then count the (days) and observe fast on the 9th. I said to him: Is it how the Messenger of Allah observed the fast? He said: Yes.
وَحَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا وَكِيعُ بْنُ الْجَرَّاحِ، عَنْ حَاجِبِ بْنِ عُمَرَ، عَنِ الْحَكَمِ بْنِ الأَعْرَجِ، قَالَ انْتَهَيْتُ إِلَى ابْنِ عَبَّاسٍ - رضى الله عنهما - وَهُوَ مُتَوَسِّدٌ رِدَاءَهُ فِي زَمْزَمَ فَقُلْتُ لَهُ أَخْبِرْنِي عَنْ صَوْمِ عَاشُورَاءَ . فَقَالَ إِذَا رَأَيْتَ هِلاَلَ الْمُحَرَّمِ فَاعْدُدْ وَأَصْبِحْ يَوْمَ التَّاسِعِ صَائِمًا . قُلْتُ هَكَذَا كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم يَصُومُهُ قَالَ نَعَمْ .
also referenced under: Book 13, Hadith 170 (In-Book) & Book 6, Hadith 2526 (USC-MSA)
Hakam b. 'Araj reported: I asked Ibn Abbas (Allah be pleased with them) as he was reclining using his cloak as a pillow near Zamzam about fasting on 'Ashura. The rest of the hadith is the same.
وَحَدَّثَنِي مُحَمَّدُ بْنُ حَاتِمٍ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ الْقَطَّانُ، عَنْ مُعَاوِيَةَ بْنِ عَمْرٍو، حَدَّثَنِي الْحَكَمُ بْنُ الأَعْرَجِ، قَالَ سَأَلْتُ ابْنَ عَبَّاسٍ - رضى الله عنهما - وَهُوَ مُتَوَسِّدٌ رِدَاءَهُ عِنْدَ زَمْزَمَ عَنْ صَوْمِ عَاشُورَاءَ . بِمِثْلِ حَدِيثِ حَاجِبِ بْنِ عُمَرَ .
also referenced under: Book 13, Hadith 171 (In-Book) & Book 6, Hadith 2527 (USC-MSA)