It is narrated from Sayyiduna Abu Mas’ud (may Allah be pleased with him) that one day I was beating one of my slaves when I heard a voice from behind me three times,“O Abu Mas’ud! Remember!”I turned around and saw that it was the Prophet (peace and blessings of Allah be upon him). He (peace be upon him) said:“By Allah! You have as much power over this slave as Allah has more power over you.”At that very moment, I swore that I would never beat any slave again.