The book of James is traditionally considered to be written by James, the brother of Jesus. (The author of this book is not to be confused with the disciple James, the brother of John, who were both disciples of Jesus.)
There is a tendency to misunderstand the book of James as setting aside following Jesus by faith and instead earning his favor through good deeds (sometimes referred to as “works”). This is not the case, as he clearly explains in the second chapter (James 2:14-26).
The purpose of this book is to combat the false understanding (heresy) that faith is merely an intellectual exercise and is not connected with a change in behavior.