Sunan an-Nasa'i 2401
'Abduallah bin amr bin Al-'As said:
"The Messenger of Allah heard that I was fasting continually and praying all night." Either he sent for him, or he happened to meet him and he said: "Have I not been told that you fast and never break your fast, and you pray all night? Do not do that, for  do that, for your eyes should have a share, your self should have a share, and your family should have a share. Fast and break your fast; pray and sleep. Fast one day out of every ten, and your will have the reward of the other nine."  He said: " I am able to do more than that, O Messenger of Allah." He said: "Observe the fast of Dawud then."  " I said: 'How did Dawud fast, O Prophet of Allah? He said: 'He used to fast one day, and not the next, and he never fled if he met(the enemy in battle)."' He said: "How can I compare to him, O Prophet of Allah?"
أَخْبَرَنَا إِبْرَاهِيمُ بْنُ الْحَسَنِ، قَالَ حَدَّثَنَا حَجَّاجٌ، قَالَ قَالَ ابْنُ جُرَيْجٍ سَمِعْتُ عَطَاءً، يَقُولُ إِنَّ أَبَا الْعَبَّاسِ الشَّاعِرَ أَخْبَرَهُ أَنَّهُ، سَمِعَ عَبْدَ اللَّهِ بْنَ عَمْرِو بْنِ الْعَاصِ، قَالَ بَلَغَ النَّبِيَّ صلى الله عليه وسلم أَنِّي أَصُومُ أَسْرُدُ الصَّوْمَ وَأُصَلِّي اللَّيْلَ فَأَرْسَلَ إِلَيْهِ وَلَمَّا لَقِيَهُ قَالَ ‏"‏ أَلَمْ أُخْبَرْ أَنَّكَ تَصُومُ وَلاَ تُفْطِرُ وَتُصَلِّي اللَّيْلَ فَلاَ تَفْعَلْ فَإِنَّ لِعَيْنِكَ حَظًّا وَلِنَفْسِكَ حَظًّا وَلأَهْلِكَ حَظًّا وَصُمْ وَأَفْطِرْ وَصَلِّ وَنَمْ وَصُمْ مِنْ كُلِّ عَشْرَةِ أَيَّامٍ يَوْمًا وَلَكَ أَجْرُ تِسْعَةٍ ‏"‏ ‏.‏ قَالَ إِنِّي أَقْوَى لِذَلِكَ يَا رَسُولَ اللَّهِ ‏.‏ قَالَ ‏"‏ صُمْ صِيَامَ دَاوُدَ إِذًا ‏"‏ ‏.‏ قَالَ وَكَيْفَ كَانَ صِيَامُ دَاوُدَ يَا نَبِيَّ اللَّهِ قَالَ ‏"‏ كَانَ يَصُومُ يَوْمًا وَيُفْطِرُ يَوْمًا وَلاَ يَفِرُّ إِذَا لاَقَى ‏"‏ ‏.‏ قَالَ وَمَنْ لِي بِهَذَا يَا نَبِيَّ اللَّهِ ‏.‏