Leviticus 19:11-13 (KJV)
11 Ye shall not steal, neither deal falsely, neither lie one to another.
12 And ye shall not swear by my name falsely, neither shalt thou profane the name of thy God: I am the Lord.
13 Thou shalt not defraud thy neighbour, neither rob him: the wages of him that is hired shall not abide with thee all night until the morning.
The Two Greatest Commandments
The two greatest commandments were part of the old law. They help us love God and our neighbor as ourselves.