According to Martin Luther King Jr. “A just law is a man made code that squares with the moral law or the law of God. An unjust law is a code that is out of harmony with the moral law.” Martin stated in the letter from Birmingham jail, Martin makes a distinction between Ius Gentium and Ius Naturalis that shares close resemblance to the philosophy of the Romans during their time. Ius Gentium is a law that is universally practice. For example, when someone buys a certain product, they have to pay for it. Stealing is not allowed, neither is murder. In the time of the Romans, however, slavery was universally used and accepted as well. Ius Naturalis means moral law. Certain things could fall under the Ius Gentium but not under Ius Naturalis. Although slavery was universally used in their time, the