Narrated by:Musa bin Talhah said
It was narrated that Musa bin Talhah said:"I heard Abu Dharr, at Ar-Rabadhah, saying: 'The Messenger of Allah said: if you want to fast at any time during the monthm then fast on the thirteenth, fourteenth and fifteenth."'
أَخْبَرَنَا عَمْرُو بْنُ يَزِيدَ، قَالَ حَدَّثَنَا عَبْدُ الرَّحْمَنِ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنِ الأَعْمَشِ، قَالَ سَمِعْتُ يَحْيَى بْنَ سَامٍ، عَنْ مُوسَى بْنِ طَلْحَةَ، قَالَ سَمِعْتُ أَبَا ذَرٍّ، بِالرَّبَذَةِ قَالَ قَالَ لِي رَسُولُ اللَّهِ صلى الله عليه وسلم " إِذَا صُمْتَ شَيْئًا مِنَ الشَّهْرِ فَصُمْ ثَلاَثَ عَشْرَةَ وَأَرْبَعَ عَشْرَةَ وَخَمْسَ عَشْرَةَ " .
Nesai
The Book of Fasting • Hadith 2424