(135) باب مَا جَاءَ فِي الْمَمْلُوكِ إِذَا نَصَحَ
'Abd Allah b. 'Umar reported the Messenger of Allah (May peace be upon him) as saying:
when a slave acts sincerely towards his master and worship Allah well, he will have a double reward.
Reference: Sunan Abi Dawud 5169
In-book reference: Book 43, Hadith 397
English translation: Book 42, Hadith 5150