John Calvin believed that Roman law was a good example of natural law, even though it wasn't perfect. He used Roman law to help him understand the laws in the Bible. Calvin thought that Roman law showed principles of natural law, so he used it to figure out which laws in the Bible were natural and which were specific to that time. He also compared Roman law to the Ten Commandments and thought that some of the laws in the Bible were similar to Roman and natural laws. However, Calvin didn't completely agree with Roman law because he thought it didn't always match up with what the Bible said or with natural law principles.