Bulugh al-Maram, Book 6, Hadith 789 (English)

Ibn ‘Umar (RAA) narrated that ‘Al-’Abbas bin 'Abdul Muttalib asked permission from the Prophet to stay at Makkah during the nights of Mina in order to provide drinking water (from Zamzam) to the pilgrims, and the Prophet allowed him.’ Agreed Upon.

وَعَنِ اِبْنِ عُمَرَ رَضِيَ اَللَّهُ عَنْهُمَا: { أَنَّ اَلْعَبَّاسَ بْنَ عَبْدِ اَلْمُطَّلِبِ ‏- رضى الله عنه ‏- اِسْتَأْذَنَ رَسُولَ اَللَّهِ ‏- صلى الله عليه وسلم ‏-أَنْ يَبِيتَ بِمَكَّةَ لَيَالِيَ مِنًى, مِنْ أَجْلِ سِقَايَتِهِ, فَأَذِنَ لَهُ } مُتَّفَقٌ عَلَيْهِ 1‏.‏ ‏1 ‏- صحيح.‏ رواه البخاري ( 1634 )‏، ومسلم ( 1315 )‏.‏

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also referenced under: Book 6, Hadith 62 (In-Book)