Riyad as-Salihin, Book 1, Hadith 228 (In-Book)

Abu Hurairah (May Allah bepleased with him) reported: Messenger of Allah said, "When one of you leads the Salat, he should not prolong it because the congregation includes those who are feeble, ill or old". One version adds: "those who have to attend to work") While offering prayers alone, you may pray as long as you like".[Al-Bukhari and Muslim].

وعن أبي هريرة رضي الله عنه ، أن رسول الله صلى الله عليه وسلم قال‏:‏ ‏"‏إذا صلى أحدكم للناس، فليخفف، فإن فيهم الضعيف والسقيم والكبير‏.‏ وإذا صلى لنفسه فليطول ما شاء‏"‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏ ‏.‏ (10)

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