Mishkat al-Masabih
‘Abdallah b. ‘Amr reported God’s Messenger as saying, “The prayer dearest to God is David’s and the fasting dearest to God is David’s. He would sleep half the night, get up to pray for a third of it, then sleep the remaining sixth; and he would fast on alternate days." (Bukhari and Muslim.)
وَعَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «أَحَبُّ الصَّلَاةِ إِلَى اللَّهِ صَلَاةُ دَاوُدَ وَأَحَبُّ الصِّيَامِ إِلَى اللَّهِ صِيَامُ دَاوُدَ كَانَ يَنَامُ نِصْفَ اللَّيْلِ وَيَقُومُ ثُلُثَهُ وَيَنَامُ سُدُسَهُ وَيَصُومُ يَوْمًا وَيُفْطِرُ يَوْمًا»
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