Riyad as-Salihin, Book 12, Hadith 1362 (In-Book)

Ibn 'Umar (May Allah be pleased with them) reported: I heard the Messenger of Allah saying, "When a slave is sincere to his master and worships Allah well, He will have a double reward." [Al-Bukhari and Muslim].

عن ابن عمر رضي الله عنهما أن رسول الله صلى الله عليه وسلم قال‏:‏ ‏ "‏إن العبد إذا نصح لسيده، وأحسن عبادة الله، فله أجره مرتين‏" ‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏

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