Sahih al-Bukhari 4507
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · "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)
Narrated Salama:
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 .
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.