Mishkat al-Masabih #1975
mishkat_al_masabih:1975عَنِ ابْنِ عَبَّاسٍ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَدِمَ الْمَدِينَةِ فَوَجَدَ الْيَهُودَ صِيَامًا يَوْمَ عَاشُورَاءَ فَقَالَ لَهُمْ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «مَا هَذَا الْيَوْمُ الَّذِي تَصُومُونَهُ؟» فَقَالُوا: هَذَا يَوْمٌ عَظِيمٌ: أَنْجَى اللَّهُ فِيهِ مُوسَى وَقَوْمَهُ وَغَرَّقَ فِرْعَوْنَ وَقَوْمَهُ فَصَامَهُ مُوسَى شُكْرًا فَنَحْنُ نَصُومُهُ فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «فَنَحْنُ أَحَقُّ وَأَوْلَى بِمُوسَى مِنْكُمْ» فَصَامَهُ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَأَمَرَ بصيامه
Ibn ‘Abbas said that God’s messenger came to Medina and found the Jews observing the fast on the day of ‘Ashura’, so he asked them what was the significance of that day which they were observing and they replied, “It is a great day on which God delivered Moses and his people and drowned Pharaoh and his people; so Moses observed it as a fast out of gratitude, and we do so also.” He said, “We have more right, and we have a closer connection with Moses than you have,” so God’s messenger observed it as a fast himself and gave orders that it should be observed. (Bukhari and Muslim.)
رسول الله قدم المدينة فوجد اليهود صياما يوم عاشوراء فقال لهم رسول الله
ابن عباس