Themes in The Grapes of WrathThere are several themes in The Grapes of Wrath, by John Steinbeck. Here I will go in depth on those. The three main themes of the story are free will versus necessity, the sanctity of every man, and the kinship of all men. The main theme (and the most important, in my opinion) is free will versus necessity. Throughout the story, characters are forced to do something because they want to or because they have to. A good example would be for mom to burn her old souvenirs when they leave for California. He doesn't want to do it (free will), but he knows he has to (necessity), since they don't have enough space to take them with him. Another example of this would be Jim Casy sacrificing himself in place of Tom for tripping the police officer. He was thinking about how to repay the Joads for their kindness (he was willing, that's the free will part). When he sees the opportunity present himself, he feels obliged to help (necessity) while accepting the blame. Another important theme in the story is the holiness of every man. This is what Casy came to believe after spending a lot of time thinking about it. He came to believe that every man was holy, and therefore had no need of sermons, since he was already holy. He began to think that everyone's soul came from the Oversoul when they were born, and that their soul returned to the Oversoul when they died. This is one of the reasons why Jim Casy was so generous; his soul was already a part of the Oversoul, so he might as well go on and do good deeds (though I'm not sure that's exactly what he thought). Throughout the book, the theme of all men's kinship is reinforced. Traveling to California should be for family only. Then, they are joined by Jim Casy. After a while they join the Wilson family.