NASAI-KUBRA 2848:
from Ibn ʿAbbās —
[Machine] The Messenger of Allah ﷺ arrived in Medina and found the Jews fasting on the day of Ashura. He asked them, "What is this?" They replied, "This is the day on which Allah saved Musa (Moses) and drowned Pharaoh. So, Musa fasted out of gratitude to Allah, and we also fast on this day." The Messenger of Allah ﷺ said, "We have more right to Musa and are closer to him than you are." So, he fasted on that day and commanded others to do so. [231] 2849 Isma'il ibn Ya'qub al-Harrani as-Sabihi reported to us, saying: Ibn Musa, the son of A'yan, reported to us, saying: My father reported to us from al-Harith, meaning the son of 'Umayr, from Ayyub, from Abdullah ibn Sa'id ibn Jubayr, from his father, from Ibn Abbas of similar account.
الكبرى للنسائي ٢٨٤٨:
عن ابن عباس —
قَدِمَ رَسُولُ اللهِ ﷺ الْمَدِينَةَ فَوَجَدَ الْيَهُودَ يَصُومُونَ يَوْمَ عَاشُورَاءَ فَسَأَلَهُمْ مَا هَذَا؟ فَقَالُوا يَوْمٌ أَنْجَى اللهُ فِيهِ مُوسَى وَأَغْرَقَ فِيهِ فِرْعَوْنَ فَصَامَهُ مُوسَى شُكْرًا لِلَّهِ فَنَحْنُ نَصُومُهُ فَقَالَ رَسُولُ اللهِ ﷺ «فَنَحْنُ أَحَقُّ بِمُوسَى وَأَوْلَى بِصِيَامِهِ» فَصَامَهُ وَأَمَرَ بِصِيَامِهِ [231] 2849 أَخْبَرَنَا إِسْمَاعِيلُ بْنُ يَعْقُوبَ الْحَرَّانِيُّ الصَّبِيحِيُّ قَالَ حَدَّثَنَا ابْنُ مُوسَى وَهُوَ ابْنُ أَعْيَنَ قَالَ حَدَّثَنَا أَبِي عَنِ الْحَارِثِ يَعْنِي ابْنَ عُمَيْرٍ عَنْ أَيُّوبَ عَنْ عَبْدِ اللهِ بْنِ سَعِيدِ بْنِ جُبَيْرٍ عَنْ أَبِيهِ عَنِ ابْنِ عَبَّاسٍ نَحْوَهُ
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