Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Bukhari :: Book 6 :: Volume 60 :: Hadith 34
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.