Riyad as-Salihin, Book 3, Hadith 773 (In-Book)

Abu Qatadah (May Allah be pleased with him) reported: Messenger of Allah said, "He who serves others with drinking water should be the last to drink himself." [At-Tirmidhi].

عن أبى قتادة رضى الله عنه عن النبي صلى الله عليه وسلم قال‏:‏ ‏ "‏ ساقي القوم آخرهم شرباً‏" ‏

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