Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
ahmad:20321 – Rawḥ > Shuʿbah > Anas b. Sīrīn > ʿAbd al-Malik b. al-Minhāl from his father

[Machine] And he was among the companions of the Messenger of Allah ﷺ who said: The Messenger of Allah ﷺ used to command us to fast the three white days (13th, 14th, and 15th of each lunar month) and he would say, "These are the fasting of a lifetime."  

أحمد:٢٠٣٢١ – حَدَّثَنَا رَوْحٌ حَدَّثَنَا شُعْبَةُ قَالَ سَمِعْتُ أَنَسَ بْنَ سِيرِينَ قَالَ سَمِعْتُ عَبْدَ الْمَلِكِ بْنَ الْمِنْهَالِ يُحَدِّثُ عَنْ أَبِيهِ قَالَ

وَكَانَ مِنْ أَصْحَابِ رَسُولِ اللهِ ﷺ قَالَ كَانَ رَسُولُ اللهِ ﷺ يَأْمُرُنَا بِصِيَامِ أَيَّامِ الْبِيضِ الثَّلَاثَةِ وَيَقُولُ هُنَّ صِيَامُ الدَّهْرِ  

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Collected by Aḥmad
ahmad:20319 – Bahz > Shuʿbah > Anas b. Sīrīn > ʿAbd al-Malik a man from Banī Qays b. Thaʿlabah from his father

[Machine] The translation of the passage into English is:

"The Messenger of Allah, ﷺ , used to command them to fast the white days and he would say, 'They are the fasting of the month,' or he said, 'of the lifetime.'"  

أحمد:٢٠٣١٩ – حَدَّثَنَا بَهْزٌ حَدَّثَنَا شُعْبَةُ حَدَّثَنِي أَنَسُ بْنُ سِيرِينَ عَنْ عَبْدِ الْمَلِكِ رَجُلٍ مِنْ بَنِي قَيْسِ بْنِ ثَعْلَبَةَ عَنْ أَبِيهِ

أَنَّ رَسُولَ اللهِ ﷺ كَانَ يَأْمُرُهُمْ بِصِيَامِ أَيَّامِ الْبِيضِ وَيَقُولُ هُنَّ صِيَامُ الشَّهْرِ أَوْ قَالَ الدَّهْرِ