The Book of Fasting
22/83. Chapter:
How to Fast Three Days of Each Month, And Mentioning The Differences Reported by The Narrators In The Narration Regarding that
Sunan an-Nasai
أَخْبَرَنَا الْحَسَنُ بْنُ مُحَمَّدٍ الزَّعْفَرَانِيُّ، قَالَ حَدَّثَنَا سَعِيدُ بْنُ سُلَيْمَانَ، عَنْ شَرِيكٍ، عَنِ الْحُرِّ بْنِ صَيَّاحٍ، عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَصُومُ ثَلاَثَةَ أَيَّامٍ مِنْ كُلِّ شَهْرٍ يَوْمَ الاِثْنَيْنِ مِنْ أَوَّلِ الشَّهْرِ وَالْخَمِيسَ الَّذِي يَلِيهِ ثُمَّ الْخَمِيسَ الَّذِي يَلِيهِ .
It was narrated from Ibn 'Umar that: the Messenger of Allah used to fast three days of each month: Monday at the beginning of the month, the following Thursday, then the Thursday after that.
Reference : Sunan an-Nasa'i 2414In-book reference : Book 22, Hadith 325English translation : Vol. 3, Book 22, Hadith 2416