Now that you’ve identified your perfect reader and you’ve determined the benefit you’re offering your reader, it’s time to nail down the main idea and theme of your book. Although ‘idea’ and ‘theme’ sound like much the same thing, they have some subtle and important differences that will help you keep your book on track for the reader.


First, let’s discuss the main idea of your book – what your book is about, the general content of your story. In my example, How to Write a Book in 30 Days, the main idea is: “The process, time tested tips and practices of writing a successful nonfiction book in just 30 days.” That’s what the book is about – the nuts and bolts anyone can follow in an organized sequential way; sort of like (I hate to admit) a cookbook or instruction manual. But the main idea of the book is just the surface, the ‘as advertised’ guarantee. Do you want to write a book in 30 days? Read How to Write a Book in 30 Days.


But is a cookbook or instruction manual really what the reader is asking for? Shouldn’t there be a little something more under the surface? An ‘un-advertised’ benefit to the book? That’s where theme comes in. Your book’s theme should be felt in reader’s the gut, not in her head. The theme is the real benefit your reader is searching for. What’s the theme, then, of How to Write a book in 30 Days? Here’s my theme: “The process of writing a book is definable, finite and, most of all, achievable for any writer, regardless of previous experience – that means you! You can write a book, your book, in just 30 days.”

Do you see how the differences between ‘idea’ and ‘theme’ can be subtle but so very important?

The book Big Mountain, Bigger God tells the story of the Mullett family’s sixteen-year battle with two of their children’s congenital heart defects. The story, the insurmountable trials and pain they suffered is the ‘idea’ of the book. But the Mulletts learned a profound lesson in the midst of this ‘no-win’ battle – that God’s ways are far greater than man’s circumstance and that God’s grace, mercy, and strength are sufficient, even when we don’t understand the why of innocent suffering. That is the ‘theme’ of Big Mountain Bigger God. The theme is what comes to reside in the reader’s heart.

Take a moment and a blank sheet of paper and ask yourself:

1) What is my main idea?  What is this book about?

2) What is my theme? What truth do I want to plant in my reader’s heart?

If it’s easier, think of it this way – your idea is the carrier, your theme is the thing you’re carrying. Your idea is the treasure chest, your theme is the treasure.

Now get to work!


Click here for “How to write a book in 30 days” step 9: “Research”