Riyad as-Salihin, Book 8, Hadith 971 (In-Book)

Jabir (May Allah be pleased with him) reported: The Messenger of Allah used to lag behind while travelling and urge the weak to walk quickly. He used to take up someone behind him and make supplication for him.[Abu Dawud].

وعنه قال‏:‏ كان رسول الله صلى الله عليه وسلم يتخلف في المسير، فيزجي الضعيف ويردف ويدعو له، ‏(‏‏(‏رواه أبو داود بإسناد حسن‏)‏‏)‏‏.‏

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