Bulugh al-Maram, Book 6, Hadith 73 (In-Book)

A’ishah (RAA) narrated, 'The Messenger of Allah went to visit. Duba’ah bint Az-Zubair bin 'Abdul Muttalib. She said to him, ‘O Messenger of Allah I have made the intention to perform Hajj but I am suffering from an illness.’ He said to her, “Perform Hajj but set a condition that you shall be relieved of the Ihram whenever you are prevented (due to illness, etc.).” Agreed upon.

وَعَنْ عَائِشَةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: { دَخَلَ اَلنَّبِيُّ ‏- صلى الله عليه وسلم ‏-عَلَى ضُبَاعَةَ بِنْتِ اَلزُّبَيْرِ بْنِ عَبْدِ اَلْمُطَّلِبِ رَضِيَ اَللَّهُ عَنْهَا, فَقَالَتْ: يَا رَسُولَ اَللَّهِ! إِنِّي أُرِيدُ اَلْحَجَّ, وَأَنَا شَاكِيَةٌ، فَقَالَ اَلنَّبِيُّ ‏- صلى الله عليه وسلم ‏- " حُجِّي وَاشْتَرِطِي: أَنَّ مَحَلِّي 1‏ حَيْثُ حَبَسْتَنِي " } مُتَّفَقٌ عَلَيْهِ.‏ 2‏.‏ ‏1 ‏- أي : تحللي من الإحرام.‏‏2 ‏- صحيح.‏ رواه البخاري ( 5089 )‏، ومسلم ( 1207 )‏.‏

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also referenced under: Book 6, Hadith 800 (English)