Narrator:Abdullah ibn Amr
حَدَّثَنَا أَبُو الْيَمَانِ، أَخْبَرَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، قَالَ أَخْبَرَنِي سَعِيدُ بْنُ الْمُسَيَّبِ، وَأَبُو سَلَمَةَ بْنُ عَبْدِ الرَّحْمَنِ أَنَّ عَبْدَ اللَّهِ بْنَ عَمْرٍو، قَالَ أُخْبِرَ رَسُولُ اللَّهِ صلى الله عليه وسلم أَنِّي أَقُولُ وَاللَّهِ لأَصُومَنَّ النَّهَارَ، وَلأَقُومَنَّ اللَّيْلَ، مَا عِشْتُ. فَقُلْتُ لَهُ قَدْ قُلْتُهُ بِأَبِي أَنْتَ وَأُمِّي. قَالَ " فَإِنَّكَ لاَ تَسْتَطِيعُ ذَلِكَ،
فَصُمْ وَأَفْطِرْ، وَقُمْ وَنَمْ، وَصُمْ مِنَ الشَّهْرِ ثَلاَثَةَ أَيَّامٍ، فَإِنَّ الْحَسَنَةَ بِعَشْرِ أَمْثَالِهَا، وَذَلِكَ مِثْلُ صِيَامِ الدَّهْرِ "
‘Abdullāh ibn ‘Amr ibn al-‘Ās (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) was told that I had said: "By Allah, I will fast every day and pray every night for as long as I live." The Messenger (may Allah's peace and blessings be upon him) asked me: "Are you the one who said that?" I said: "Yes, I said it; by my father, you and my mother." He said: "You would not be able to do that. So fast and break your fast, pray and sleep. Fast for three days a month. The reward of a good deed is multiplied by ten, so the fasting of three days a month equals the fasting of a year." I said: "I can do (fast) more than this." He said: "Fast one day every three days." I said: "I can do more than that." He said: "Fast every other day; this was the fasting of Dawūd and the best form of fasting." I said: "I can do better than that." He said: "There is nothing better than that." In another narration, the Prophet (may Allah's peace and blessings be upon him) said: "There is no fasting superior to the fast of my brother Dawūd; fasting half of one's life by fasting one day and eating one day."
Reported by Al-Bukhari (No. 1976, 1131, 3418, 3420), Muslim (No. 1159a, 1159f, 1159k), Abu Dawud (No. 2427, 2448), An-Nasa’i (No. 1630, 2344, 2392, 2401), Ibn Majah (No. 1712), Ahmad (No. 6203, 6471, 6579) and Ad-Darimi (No. 1687).