The Messenger of Allah ﷺ used to fast three days every month. (Using translation from Abū Dāʾūd 2450)   

أَنَّ رَسُولَ اللهِ ﷺ كَانَ يَصُومُ ثَلَاثَةَ أَيَّامٍ مِنْ غُرَّةِ كُلِّ شَهْرٍ  

[Machine] I did not see the Messenger of Allah ﷺ break his fast on a Friday. Abu Abdullah Al-Hafiz and Abu Uthman Saeed ibn Muhammad ibn Muhammad ibn Abdan and Abu Al-Hasan Ali ibn Muhammad Al-Sab'i narrated to us, and they said: Abu Al-Abbas Al-Asamm narrated to us, and he said: Al-Abbas ibn Muhammad Al-Duri informed me that Ali ibn Al-Hasan ibn Shaqiq narrated to me, and he said: Abu Hamza Al-Sukkari narrated to me, and he said: Asim ibn Bahdala mentioned it to me in its meaning and said: "And say that he never used to miss fasting on a Friday."  

مَا رَأَيْتُ رَسُولَ اللهِ ﷺ مُفْطِرًا يَوْمَ الْجُمُعَةِ 8441 وَأَخْبَرَنَا أَبُو عَبْدِ اللهِ الْحَافِظُ وَأَبُو عُثْمَانَ سَعِيدُ بْنُ مُحَمَّدِ بْنِ مُحَمَّدِ بْنِ عَبْدَانَ وَأَبُو الْحَسَنِ عَلِيُّ بْنُ مُحَمَّدٍ السُّبْعِيُّ قَالُوا ثنا أَبُو الْعَبَّاسِ الْأَصَمُّ ثنا الْعَبَّاسُ بْنُ مُحَمَّدٍ الدُّورِيُّ أنبأ عَلِيُّ بْنُ الْحَسَنِ بْنِ شَقِيقٍ ثنا أَبُو حَمْزَةَ السُّكَّرِيُّ ثنا عَاصِمُ بْنُ بَهْدَلَةَ فَذَكَرَهُ بِمَعْنَاهُ وَقَالَ وَقُلْ مَا كَانَ يَفُوتُهُ صَوْمُ يَوْمِ الْجُمُعَةِ  

The Messenger of Allah ﷺ used to command us to fast the days of the white (nights): thirteenth, fourteenth and fifteenth of the month. He said: This is like keeping perpetual fast. (Using translation from Abū Dāʾūd 2449)   

كَانَ رَسُولُ اللهِ ﷺ يَأْمُرُنَا أَنْ نَصُومَ الْبِيضَ ثَلَاثَ عَشْرَةَ وَأَرْبَعَ عَشْرَةَ وَخَمْسَ عَشْرَةَ وَقَالَ هِيَ كَهَيْئَةِ الدَّهْرِ  

[Machine] And he (Abdullah ibn Abbas) was among the companions of the Prophet ﷺ who said: The Messenger of Allah ﷺ used to command us to fast the three white days (13th, 14th, and 15th of every lunar month) and he would say, "These are the fasting of the whole year." Al-Abbas said: This is what has been narrated in a hadith by Shu'bah from Abdul-Malik ibn Minhal, he said: The scholar (Shu'bah) narrated to us from Yahya ibn Ma'een that he said: This is a mistake, it is actually Abd al-Malik ibn Qatadah ibn Milhan Al-Qaysi.  

وَكَانَ مِنْ أَصْحَابِ النَّبِيِّ ﷺ قَالَ كَانَ رَسُولُ اللهِ ﷺ يَأْمُرُنَا بِصِيَامِ أَيَّامِ الْبِيضِ الثَّلَاثَةِ وَيَقُولُ هُنَّ صِيَامُ الدَّهْرِ قَالَ الْعَبَّاسُ هَكَذَا قَالَ رَوْحٌ فِي حَدِيثِ شُعْبَةَ عَنْ عَبْدِ الْمَلِكِ بْنِ الْمِنْهَالِ قَالَ الشَّيْخُ وَرُوِّينَا عَنْ يَحْيَى بْنِ مَعِينٍ أَنَّهُ قَالَ هَذَا خَطَأٌ إِنَّمَا هُوَ عَبْدُ الْمَلِكِ بْنُ قَتَادَةَ بْنِ مِلْحَانَ الْقَيْسِيُّ  

"The Messenger of Allah commanded us to fast the three days of Al-Bid, the thirteenth, fourteenth and fifteenth." (Using translation from Nasāʾī 2422)   

أَمَرَنَا رَسُولُ اللهِ ﷺ بِصِيَامِ ثَلَاثَةِ أَيَّامِ الْبِيضِ ثَلَاثَ عَشْرَةَ وَأَرْبَعَ عَشْرَةَ وَخَمْسَ عَشْرَةَ  

[Machine] The Messenger of Allah ﷺ said, "O Abu Dharr, if you fast three days every month, then fast on the thirteenth, fourteenth, and fifteenth." It was also narrated by others from Musa ibn Talhah from Ibn al-Hawtakiyyah from Abu Dharr, and it was said that it was narrated by Abu Musa from Abu Hurairah.  

قَالَ رَسُولُ اللهِ ﷺ يَا أَبَا ذَرٍّ إِذَا صُمْتَ مِنَ الشَّهْرِ ثَلَاثَةَ أَيَّامٍ فَصُمْ ثَلَاثَ عَشْرَةَ وَأَرْبَعَ عَشْرَةَ وَخَمْسَ عَشْرَةَ وَرَوَاهُ غَيْرُهُ عَنْ مُوسَى بْنِ طَلْحَةَ عَنِ ابْنِ الْحَوْتَكِيَّةِ عَنْ أَبِي ذَرٍّ وَقِيلَ عَنْ أَبِي مُوسَى عَنْ أَبِي هُرَيْرَةَ  

The apostle of Allah ﷺ used to fast three days every month: Monday, Thursday and Monday in the next week. (Using translation from Abū Dāʾūd 2451)   

كَانَ رَسُولُ اللهِ ﷺ يَصُومُ ثَلَاثَةَ أَيَّامٍ مِنَ الشَّهْرِ الِاثْنَيْنِ وَالْخَمِيسَ وَالِاثْنَيْنِ مِنَ الْجُمُعَةِ الْأُخْرَى  

[Machine] The Messenger of Allah ﷺ used to command me to fast three days from the month: Monday, Thursday, and Thursday.  

كَانَ رَسُولُ اللهِ ﷺ يَأْمُرُنِي أَنْ أَصُومَ ثَلَاثَةَ أَيَّامٍ مِنَ الشَّهْرِ الِاثْنَيْنِ وَالْخَمِيسَ وَالْخَمِيسَ