Riyad as-Salihin 1364
Abu Musa Al-Ash'ari (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) said, "A slave who worships his Rubb (Allah) well and discharges efficiently and faithfully the duties which are assigned to him by his master, will have a double reward." [Al-Bukhari] .
وعن أبي موسى الأشعري قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏
"‏المملوك الذي يحسن عبادة ربه ويؤدي إلى سيده الذي عليه من الحق، والنصيحة والطاعة له أجران‏"‏ ‏(‏‏(‏رواه البخاري‏)‏‏)‏‏.‏