Sahih al-Bukhari, Hadith 1945 ⓘ
Narrated Abu Ad-Darda: We set out with Allah's Messenger on one of his journeys on a very hot day, and it was so hot that one had to put his hand over his head because of the severity of heat. None of us was fasting except the Prophet and Ibn Rawaha.
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، حَدَّثَنَا يَحْيَى بْنُ حَمْزَةَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ يَزِيدَ بْنِ جَابِرٍ، أَنَّ إِسْمَاعِيلَ بْنَ عُبَيْدِ اللَّهِ، حَدَّثَهُ عَنْ أُمِّ الدَّرْدَاءِ، عَنْ أَبِي الدَّرْدَاءِ ـ رضى الله عنه ـ قَالَ خَرَجْنَا مَعَ النَّبِيِّ صلى الله عليه وسلم فِي بَعْضِ أَسْفَارِهِ فِي يَوْمٍ حَارٍّ حَتَّى يَضَعَ الرَّجُلُ يَدَهُ عَلَى رَأْسِهِ مِنْ شِدَّةِ الْحَرِّ، وَمَا فِينَا صَائِمٌ إِلاَّ مَا كَانَ مِنَ النَّبِيِّ صلى الله عليه وسلم وَابْنِ رَوَاحَةَ.
also referenced under: Book 30, Hadith 52 (In-Book) & Volume 3, Book 31, Hadith 166 (USC-MSA)