كتاب الصيام
13  
The Book of Fasting
(36)
Chapter: It is recommended to fast three days of every month, and to fast on the days of 'Arafah and 'Ashura', and to fast on Mondays and Thursdays
(36)
باب اسْتِحْبَابِ صِيَامِ ثَلَاثَةِ أَيَّامٍ مِنْ كُلِّ شَهْرٍ وَصَوْمِ يَوْمِ عَرَفَةَ وَعَاشُورَاءَ وَالِاثْنَيْنِ وَالْخَمِيسِ
Sahih Muslim 1162 b

Abu Qatada al-Ansari (Allah be pleased with him) reported that the Messenger of Allah (ﷺ) was asked about his fasting. The Messenger of Allah (ﷺ) felt annoyed. Thereupon 'Umar (Allah be pleased with him) said:

We are pleased with Allah as the Lord, with Islam as our Code of Life, with Muhammad as the Messenger and with our pledge (to you for willing and cheerful submission) as a (sacred) commitment. He was then asked about perpetual fasting, whereupon he said: He neither fasted nor did he break it, or he did not fast and he did not break it. He was then asked about fasting for two days and breaking one day. He (the Holy Prophet) said: And who has strength enough to do it? He was asked about fasting for a day and breaking for two days, whereupon he said: May Allah bestow upon us strength to do it. He was then asked about fasting for a day and breaking on the other, whereupon he said: That is the fasting of my brother David (peace be upon him). He was then asked about fasting on Monday, whereupon he said: It was the day on which I was born. on which I was commissioned with prophethood or revelation was sent to me, (and he further) said: Three days' fasting every month and of the whole of Ramadan every year is a perpetual fast. He was asked about fasting on the day of 'Arafa (9th of Dhu'I-Hijja), whereupon he said: It expiates the sins of the preceding year and the coming year. He was asked about fasting on the day of 'Ashura (10th of Muharram), whereupon be said: It expiates the sins of the preceding year. (Imam Muslim said that in this hadith there is a) narration of Imam Shu'ba that he was asked about fasting on Monday and Thursday, but we (Imam Muslim) did not mention Thursday for we found it as an error (in reporting).
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَمُحَمَّدُ بْنُ بَشَّارٍ، - وَاللَّفْظُ لاِبْنِ الْمُثَنَّى - قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ غَيْلاَنَ بْنِ جَرِيرٍ، سَمِعَ عَبْدَ اللَّهِ بْنَ مَعْبَدٍ الزِّمَّانِيَّ، عَنْ أَبِي قَتَادَةَ الأَنْصَارِيِّ، رضى الله عنه أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم سُئِلَ عَنْ صَوْمِهِ قَالَ فَغَضِبَ رَسُولُ اللَّهِ صلى الله عليه وسلم فَقَالَ عُمَرُ رضى الله عنه رَضِينَا بِاللَّهِ رَبًّا وَبِالإِسْلاَمِ دِينًا وَبِمُحَمَّدٍ رَسُولاً وَبِبَيْعَتِنَا بَيْعَةً ‏.‏ قَالَ فَسُئِلَ عَنْ صِيَامِ الدَّهْرِ فَقَالَ ‏"‏ لاَ صَامَ وَلاَ أَفْطَرَ ‏"‏ ‏.‏ أَوْ ‏"‏ مَا صَامَ وَمَا أَفْطَرَ ‏"‏ ‏.‏ قَالَ فَسُئِلَ عَنْ صَوْمِ يَوْمَيْنِ وَإِفْطَارِ يَوْمٍ قَالَ ‏"‏ وَمَنْ يُطِيقُ ذَلِكَ ‏"‏ ‏.‏ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمٍ وَإِفْطَارِ يَوْمَيْنِ قَالَ ‏"‏ لَيْتَ أَنَّ اللَّهَ قَوَّانَا لِذَلِكَ ‏"‏ ‏.‏ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمٍ وَإِفْطَارِ يَوْمٍ قَالَ ‏"‏ ذَاكَ صَوْمُ أَخِي دَاوُدَ عَلَيْهِ السَّلاَمُ ‏"‏ ‏.‏ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمِ الاِثْنَيْنِ قَالَ ‏"‏ ذَاكَ يَوْمٌ وُلِدْتُ فِيهِ وَيَوْمٌ بُعِثْتُ أَوْ أُنْزِلَ عَلَىَّ فِيهِ ‏"‏ ‏.‏ قَالَ فَقَالَ ‏"‏ صَوْمُ ثَلاَثَةٍ مِنْ كُلِّ شَهْرٍ وَرَمَضَانَ إِلَى رَمَضَانَ صَوْمُ الدَّهْرِ ‏"‏ ‏.‏ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمِ عَرَفَةَ فَقَالَ ‏"‏ يُكَفِّرُ السَّنَةَ الْمَاضِيَةَ وَالْبَاقِيَةَ ‏"‏ ‏.‏ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمِ عَاشُورَاءَ فَقَالَ ‏"‏ يُكَفِّرُ السَّنَةَ الْمَاضِيَةَ ‏"‏ ‏.‏ وَفِي هَذَا الْحَدِيثِ مِنْ رِوَايَةِ شُعْبَةَ قَالَ وَسُئِلَ عَنْ صَوْمِ يَوْمِ الاِثْنَيْنِ وَالْخَمِيسِ فَسَكَتْنَا عَنْ ذِكْرِ الْخَمِيسِ لَمَّا نَرَاهُ وَهْمًا ‏.‏
Reference : Sahih Muslim 1162b
In-book reference : Book 13, Hadith 253
USC-MSA web (English) reference : Book 6, Hadith 2603
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