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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(26)
"So whoever of you sights (the crescent on the first night of) the month (of Ramadan, i.e., is present at his home), he must observe Saum (fast) that month... (V.2:185)
(26)
Sahih al-Bukhari 4507

Narrated Salama:

When the Divine Revelation: "For those who can fast, they had a choice either fast, or feed a poor for every day," (2.184) was revealed, it was permissible for one to give a ransom and give up fasting, till the Verse succeeding it was revealed and abrogated it.

حَدَّثَنَا قُتَيْبَةُ، حَدَّثَنَا بَكْرُ بْنُ مُضَرَ، عَنْ عَمْرِو بْنِ الْحَارِثِ، عَنْ بُكَيْرِ بْنِ عَبْدِ اللَّهِ، عَنْ يَزِيدَ، مَوْلَى سَلَمَةَ بْنِ الأَكْوَعِ عَنْ سَلَمَةَ، قَالَ لَمَّا نَزَلَتْ ‏{‏وَعَلَى الَّذِينَ يُطِيقُونَهُ فِدْيَةٌ طَعَامُ مِسْكِينٍ‏}‏ كَانَ مَنْ أَرَادَ أَنْ يُفْطِرَ وَيَفْتَدِيَ حَتَّى نَزَلَتِ الآيَةُ الَّتِي بَعْدَهَا فَنَسَخَتْهَا‏.‏ مَاتَ بُكَيْرٌ قَبْلَ يَزِيدَ‏.‏
Reference : Sahih al-Bukhari 4507
In-book reference : Book 65, Hadith 34
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 34
  (deprecated numbering scheme)