Abu Hurayrah (may Allah be pleased with him) narrated this saying of the Messenger of Allah (peace and blessings be upon him): "When a slave fulfils the right of Allah and the right of his masters, he receives a double reward." He said: I narrated this hadith to Ka'b (may Allah have mercy on him), and he said: There is no reckoning upon him, nor upon an abstinent believer of little means.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النفقات / 15810