Rambam describes in Chapter 61 the meaning of the four letter name of God and how it differs from all other names used to describe God. He also teaches how these names have no inherent magical power to accomplish anything and how it is futile to use them as magical charms. In 62 Rambam discusses the secret 12 and 42 letter names of God and how they were concealed because people were led astray by the idea that God could be described.