In this passage Paul compares the old covenant under Moses and the new covenant under Jesus. The old covenant, the law, was temporary and meant to guide us. It was a way to clarify good and bad, right and wrong, and to set boundaries. But it became something else, a way for man to earn his way into heaven by following it. But the law is not a replacement for having a relationship with the living Lord. That came with Jesus and the new covenant. Those who have received the new covenant in Christ see that the new covenant has replaced the old covenant.