IBNHIBBAN 3633:
from al-Ḥakam b. al-Aʿraj —
[Machine] "I approached Ibn Abbas while he was sitting beside his robe near Zamzam, and I sat beside him. What a wonderful companion he was! I asked him about Ashura. He sat upright and asked me, "Which aspect of it do you want to know?" I said, "I want to know about its fasting, which day do we fast?" He replied, "When you see the crescent moon of Muharram, then count and start fasting from the ninth day." I asked, "Did Muhammad ﷺ also fast in this manner?" He answered, "Yes.""
ابن حبّان ٣٦٣٣:
عن الحكم بن الاعرج —
انْتَهَيْتُ إِلَى ابْنِ عَبَّاسٍ وَهُوَ مُتَوَسِّدٌ رِدَاءَهُ عِنْدَ زَمْزَمَ فَجَلَسْتُ إِلَيْهِ وَنِعْمَ الْجَلِيسُ كَانَ فَسَأَلْتُهُ عَنْ عَاشُورَاءَ؟ فَاسْتَوَى جَالِسًا ثُمَّ قَالَ «عَنْ أَيِّ بَابِهِ تَسْأَلُ؟ » قَالَ قُلْتُ عَنْ صِيَامِهِ أَيَّ يَوْمٍ نَصُومُهُ؟ قَالَ «إِذَا رَأَيْتَ هِلَالَ الْمُحَرَّمِ فَاعْدُدْ ثُمَّ أَصْبِحْ مِنْ تَاسِعِهِ صَائِمًا» قُلْتُ أَكَذَلِكَ كَانَ يَصُومُ مُحَمَّدٌ ﷺ قَالَ «نَعَمْ»
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