Messenger of Allah ﷺ was informed about my fasts, and he came to me and I spread for him a leather cushion stuffed with palm fires, but he sat on the ground and the cushion remained between me and him, and then he said, "Isn't it sufficient for you to fast three days a month?" I replied, "O Allah's Apostle! (I can fast more)." He said, "Five?" I replied, "O Messenger of Allah ﷺ! (I can fast more)." He said, "Seven?" I replied, "O Messenger of Allah ﷺ! (I can fast more)." He said, "Nine (days per month)?" I replied, "O Messenger of Allah ﷺ! (I can fast more)" He said, "Eleven (days per month)?" And then the Prophet said, "There is no fast superior to that of the Prophet ﷺ David it was for half of the year. So, fast on alternate days."
فَحَدَّثَنَا أَنَّ رَسُولَ اللَّهِ ﷺ ذُكِرَ لَهُ صَوْمِي فَدَخَلَ عَلَىَّ فَأَلْقَيْتُ لَهُ وِسَادَةً مِنْ أَدَمٍ حَشْوُهَا لِيفٌ فَجَلَسَ عَلَى الأَرْضِ وَصَارَتِ الْوِسَادَةُ بَيْنِي وَبَيْنَهُ فَقَالَ أَمَا يَكْفِيكَ مِنْ كُلِّ شَهْرٍ ثَلاَثَةُ أَيَّامٍ قَالَ قُلْتُ يَا رَسُولَ اللَّهِ قَالَ خَمْسًا قُلْتُ يَا رَسُولَ اللَّهِ قَالَ سَبْعًا قُلْتُ يَا رَسُولَ اللَّهِ قَالَ تِسْعًا قُلْتُ يَا رَسُولَ اللَّهِ قَالَ إِحْدَى عَشْرَةَ ثُمَّ قَالَ النَّبِيُّ ﷺ لاَ صَوْمَ فَوْقَ صَوْمِ دَاوُدَ عَلَيْهِ السَّلاَمُ شَطْرَ الدَّهْرِ صُمْ يَوْمًا وَأَفْطِرْ يَوْمًا