Leviticus 25:42-46

VIN(i) 42 Because they are my servants, whom I brought out of the land of Egypt; he must not be sold as a slave. 43 "'Do not treat them harshly. Respect your God. 44 "'You may have male and female slaves, but buy them from the nations around you. 45 "'You may also buy the children of the foreigners who are living among you. Such children born in your land may become your property. 46 "'You may leave them as an inheritance to your children, whom they must serve as long as they live. But you must not treat any Israelites harshly.