Narrated Abu Dhar (may Allah be pleased with him): I abused a man by calling his mother with bad names. The Prophet (peace be upon him) said to me, “O, Abu Dhar! Did you abuse him by calling his mother with bad names? You still have some characteristics of ignorance. Your slaves are your brothers and Allah has put them under your command. So, whoever has a brother under his command should feed him of that which he eats and dress him of that which he wears. Do not ask them(slaves) to do things beyond their capacity (power) and if you do so, then help them.