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كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(33)
"...And whosoever performs the 'Umra in the months of Hajj before (performing) the Hajj (i.e., Hajj At.Tamattu' and AI-Qiran) ." (V.2:196)
(33)
Sahih al-Bukhari 4518

Narrated `Imran bin Husain:

The Verse of Hajj-at-Tamatu was revealed in Allah's Book, so we performed it with Allah's Messenger (ﷺ), and nothing was revealed in Qur'an to make it illegal, nor did the Prophet (ﷺ) prohibit it till he died. But the man (who regarded it illegal) just expressed what his own mind suggested.

حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى، عَنْ عِمْرَانَ أَبِي بَكْرٍ، حَدَّثَنَا أَبُو رَجَاءٍ، عَنْ عِمْرَانَ بْنِ حُصَيْنٍ ـ رضى الله عنهما ـ قَالَ أُنْزِلَتْ آيَةُ الْمُتْعَةِ فِي كِتَابِ اللَّهِ فَفَعَلْنَاهَا مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم، وَلَمْ يُنْزَلْ قُرْآنٌ يُحَرِّمُهُ، وَلَمْ يَنْهَ عَنْهَا حَتَّى مَاتَ قَالَ رَجُلٌ بِرَأْيِهِ مَا شَاءَ‏.‏
Reference : Sahih al-Bukhari 4518
In-book reference : Book 65, Hadith 43
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 43
  (deprecated numbering scheme)