Muwatta Malik, Book 9, Hadith 329 (In-Book)

Yahya related to me from Malik from Da'ud ibn al-Husayn from al- Araj from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, joined dhuhr and asr on his journey to Tabuk.

حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ دَاوُدَ بْنِ الْحُصَيْنِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَجْمَعُ بَيْنَ الظُّهْرِ وَالْعَصْرِ فِي سَفَرِهِ إِلَى تَبُوكَ ‏.‏

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also referenced under: Book 9, Hadith 1 (USC-MSA)