'It was said to the Prophet that a man fasted for the rest of his life. He said: 'I wish that he had never eaten.' They said: 'Two-thirds (of a lifetime)?' He said: 'That is too much.' Then he said: 'Shall I not tell you of that which will take away impurity from the heart? Fasting three days each month." 'Ata said: "someone who heard him told me that Ibn 'Umar (said) that the Prophet said: 'Whoever fasts every day of his life, then he has not fasted."  

عَنْ رَجُلٍ مِنْ أَصْحَابِ النَّبِيِّ ﷺ قَالَ قِيلَ لِلنَّبِيِّ ﷺ رَجُلٌ يَصُومُ الدَّهْرَ قَالَ وَدِدْتُ أَنَّهُ لَمْ يَطْعَمِ الدَّهْرَ قَالُوا فَثُلُثَيْهِ قَالَ أَكْثَرَ قَالُوا فَنِصْفَهُ قَالَ أَكْثَرَ ثُمَّ قَالَ أَلاَ أُخْبِرُكُمْ بِمَا يُذْهِبُ وَحَرَ الصَّدْرِ صَوْمُ ثَلاَثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ  

"A man came to the Messenger of Allah and said: 'O Messenger of Allah, what do you say about a man who fated for the rest of his life?' The Messenger of Allah said: 'I wish that he would never eat for the rest of his life.' He said: 'Two-thirds ( of a lifetime)?' he said: 'That is too much.' He said: 'Half?' He said: 'Shall I not tell you of that which will take away impurity from the heart?' He said: 'Yes.' He said: 'Fasting for three days each month."' 'Ata said: "someone who heard him told me that Ibn 'Umar (said) that the Prophet said: 'Whoever fasts every day of his life, then he has not fasted."  

أَتَى رَسُولَ اللَّهِ ﷺ رَجُلٌ فَقَالَ يَا رَسُولَ اللَّهِ مَا تَقُولُ فِي رَجُلٍ صَامَ الدَّهْرَ كُلَّهُ فَقَالَ رَسُولُ اللَّهِ ﷺ وَدِدْتُ أَنَّهُ لَمْ يَطْعَمِ الدَّهْرَ شَيْئًا قَالَ فَثُلُثَيْهِ قَالَ أَكْثَرَ قَالَ فَنِصْفَهُ قَالَ أَكْثَرَ قَالَ أَفَلاَ أُخْبِرُكُمْ بِمَا يُذْهِبُ وَحَرَ الصَّدْرِ قَالُوا بَلَى قَالَ صِيَامُ ثَلاَثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ  

"A man came to the Messenger of Allah and said: 'O Messenger of Allah, what do you say about a man who fated for the rest of his life?' The Messenger of Allah said: 'I wish that he would never eat for the rest of his life.' He said: 'Two-thirds ( of a lifetime)?' he said: 'That is too much.' He said: 'Half?' He said: 'Shall I not tell you of that which will take away impurity from the heart?' He said: 'Yes.' He said: 'Fasting for three days each month."' 'Ata said: "someone who heard him told me that Ibn 'Umar (said) that the Prophet said: 'Whoever fasts every day of his life, then he has not fasted." (Using translation from Nasāʾī 2386)  

أَتَى رَسُولَ اللهِ ﷺ رَجُلٌ فَقَالَ يَا رَسُولَ اللهِ مَا تَقُولُ فِي رَجُلٍ صَامَ الدَّهْرَ؟ فَقَالَ رَسُولُ اللهِ ﷺ «وَدِدْتُ أَنَّهُ لَمْ يَطْعَمِ الدَّهْرَ شَيْئًا» قَالَ فَثُلُثَيْهِ؟ قَالَ «أَكْثَرَ» قَالَ فَنِصْفَهُ قَالَ «أَكْثَرَ أَلَا أُخْبِرُكُمْ بِمَا يُذْهِبُ وَحَرَ الصَّدْرِ؟» قَالُوا بَلَى قَالَ «صَوْمُ ثَلَاثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ»