Abu Bakr as-Siddiq reported God’s Messenger as saying, “One who treats badly those under his authority will not enter paradise.” He was asked whether he had not told them that this people had more slaves and orphans than any other, and replied, “Yes, so treat them as generously as you treat your children and give them food out of what you eat.” They then asked what benefit they got out of the world, and he replied, “A horse which you equip to fight on it in God’s path, and a slave who serves you sufficiently; and when he prays he is your brother.”
Abu Huraira reported God’s Messenger as saying, “Let me tell you who your evil ones are. They are those who eat alone, beat their slaves, and withhold their help.”
I was brought before God’s Messenger in the year of Uhud when I was fourteen and he sent me back. Then I was brought before him in the year of the Trench when I was fifteen and he gave me permission to fight.* ‘Umar b. ‘Abd al-‘Aziz said this represents the difference between fighting men and children.
* Ajazani. It may be translated as above or it may mean “he gave me a fighting man's permission”.
(Bukhari and Muslim.)