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كتاب الاعتصام بالكتاب والسنة
96  
Holding Fast to the Qur'an and Sunnah
(5)
Chapter: Going deeply into and arguing about knowledge, and exaggerating in religion, and inventing heresies
(5)
باب مَا يُكْرَهُ مِنَ التَّعَمُّقِ وَالتَّنَازُعِ فِي الْعِلْمِ وَالْغُلُوِّ فِي الدِّينِ وَالْبِدَعِ
Sahih al-Bukhari 7299

Narrated Abu Huraira:

The Prophet (ﷺ) said (to his companions), "Do not fast Al-Wisal." They said, "But you fast Al-Wisail." He said, "I am not like you, for at night my Lord feeds me and makes me drink." But the people did not give up Al-Wisal, so the Prophet (ﷺ) fasted Al-Wisal with them for two days or two nights, and then they saw the crescent whereupon the Prophet (ﷺ) said, "If the crescent had delayed, I would have continued fasting (because of you)," as if he wanted to vanquish them completely (because they had refused to give up Al Wisal).

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، حَدَّثَنَا هِشَامٌ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ أَبِي سَلَمَةَ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ لاَ تُوَاصِلُوا ‏"‏‏.‏ قَالُوا إِنَّكَ تُوَاصِلُ‏.‏ قَالَ ‏"‏ إِنِّي لَسْتُ مِثْلَكُمْ، إِنِّي أَبِيتُ يُطْعِمُنِي رَبِّي وَيَسْقِينِي ‏"‏‏.‏ فَلَمْ يَنْتَهُوا عَنِ الْوِصَالِ ـ قَالَ ـ فَوَاصَلَ بِهِمُ النَّبِيُّ صلى الله عليه وسلم يَوْمَيْنِ أَوْ لَيْلَتَيْنِ، ثُمَّ رَأَوُا الْهِلاَلَ فَقَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ لَوْ تَأَخَّرَ الْهِلاَلُ لَزِدْتُكُمْ ‏"‏‏.‏ كَالْمُنَكِّلِ لَهُمْ‏.‏
Reference : Sahih al-Bukhari 7299
In-book reference : Book 96, Hadith 30
USC-MSA web (English) reference : Vol. 9, Book 92, Hadith 402
  (deprecated numbering scheme)