Riyad as-Salihin, Book 9, Hadith 1073 (In-Book)

Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah said, "No Salat is more burdensome to the hypocrites than the Fajr (dawn) prayer and the 'Isha' (night) prayer; and if they knew their merits, they would come to them even if they had to crawl to do so."[Al-Bukhari and Muslim].

وعنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏ "‏ليس صلاة أثقل على المنافقين من صلاة الفجر والعشاء ولو يعلمون ما فيهما لأتوهما ولو حبوًا‏" ‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏‏.‏

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