The book of Job is the 18th book in the Old Testament of the Bible.
The theme of the book is that he is a wealthy man who is living an upright and righteous life. God mentions Job to Satan and how he is a righteous man. Satan says he is only a righteous man because God is protecting him. God gives Satan permission to test him, only to not take his life.
The whole book is about that testing, the response of his “friends” and the final outcome.