'Amr said: "I spoke to the Prophet and he said: 'Fast one day out of ten and you will have the reward of the other nine.' I said: 'I am able to do more than that.' He said: 'Fast one day out of eight and you will have the reward of the other eight.' I said: 'I am able to do more than that.' He said: 'Fast one day out of eight and you will have the reward of the other seven.' I said: 'I am able to do more than that.' 'Fast one day and not the next."' (Using translation from Nasāʾī 2395)
«صُمْ مِنْ كُلِّ عَشَرَةِ أَيَّامٍ يَوْمًا وَلَكَ أَجْرُ تِلْكَ التِّسْعَةِ» فَقُلْتُ إِنِّي أَقْوَى مِنْ ذَلِكَ قَالَ «فَصُمْ مِنْ كُلِّ تِسْعَةِ أَيَّامٍ يَوْمًا وَلَكَ أَجْرُ تِلْكَ الثَّمَانِيَةِ» فَقُلْتُ إِنِّي أَقْوَى مَنْ ذَلِكَ قَالَ «فَصُمْ مِنْ كُلِّ ثَمَانِيَةِ أَيَّامٍ يَوْمًا وَلَكَ أَجْرُ تِلْكَ السَّبْعَةِ» قُلْتُ إِنِّي أَقْوَى مِنْ ذَلِكَ قَالَ فَلَمْ يَزَلْ حَتَّى قَالَ «صُمْ يَوْمًا وَأَفْطِرْ يَوْمًا»