How the “Crux Tool” Can Help You Understand Any Book of the Bible

The Crux of Each Book

Just as every Bible passage has a main point, so does every biblical book, and it’s very important to find it. The crux tool—a hermeneutical tool—can help you do that. By using it well, you can discover the message or theme of any biblical book.

Understanding This Tool

The idea of finding the main theme or big idea for an entire book of the Bible may seem intimidating because some of those books are very long. So I want to give you a few basic hints about how you can begin working to identify the crux of any book of the Bible by using this tool. This is a very important tool, and here is why: every author of the Bible was inspired by God’s Holy Spirit to write, and they wrote with a very clear purpose—a big idea. Unless we identify that big idea—that crux—for any particular book, we will become confused as we study the individual passages within that book. We need to have a good grasp of the overarching point in order to understand the points of the individual parts. The crux tool will help you do that—and will serve you well as you study smaller passages within any book.

Here are the hints that you can use to help you as you seek to pinpoint the crux of a book:

Purpose statement. You can look for a purpose statement. Some biblical authors make it very easy on us; they obviously and openly tell us why they are writing the book and what their main point will be.

Beginning and ending. You can look at how a book begins and ends. Many times, a biblical author will start by giving you an idea of the main purpose or crux of his book, then will conclude with a restatement of that point. Again, this is a very helpful way to find the crux. It’s not very different from the way that many of us were taught to write essays in school—by giving an introduction that states the main point, writing the body of the essay, and then restating the main point in the conclusion. Some biblical authors do this more explicitly than others.

Understanding God's Word

Jon Nielson

In this accessible guide to biblical interpretation, pastor Jon Nielson presents 6 hermeneutical tools and demonstrates how to use them effectively to improve personal or small-group Bible studies. 

Repetition. You can often discover words, phrases, and ideas that keep coming up throughout a book of the Bible. Many times, what the author keeps repeating is an important hint as to the overall crux of the book.

Obviously, a key part of using these three hints is actually taking some time to read through books of the Bible—even multiple times—and ideally in one sitting. The best method by which to find your way to the crux of a book is to read it again and again, and to work hard to determine the book’s shape, trajectory, and major themes. You will get better at using this tool the more you read the Bible. Don’t cheat yourself out of the experience of actually reading an entire book of the Bible all the way through; there is no shortcut to good Bible study.

Remember, this tool is a very important one for your tool belt because you cannot understand the various parts of a book unless you grasp the crux of the entire book.

Problems Avoided with This Tool

Now think about some problems in Bible interpretation and application that can be avoided when we use the crux tool well. Seeing these problems will set us up to learn about the important benefits of this tool.

What are some of the problems that can happen if we ignore the crux tool as we study biblical books?

We might get lost in our reading and understanding. Perhaps you have known the experience of getting lost in your reading or study of a particular book. If this has ever happened to you, you know that it is not fun; rather, it’s quite frustrating. It is not pleasant to be confused or to not understand what an author is doing or where he or she is going with a plot or a story. Understanding the crux of a biblical book will help you avoid getting lost as you read and study it. It will help you keep the main focus central in your mind so you can always look for the way the author is developing, expanding, or referring to that main point.

We might fail to see the right application in our study. Sometimes as we study a particular passage in the Bible, we begin to think that it is leading to a particular application for Christian actions, thoughts, or words. But we are not sure. How do we know if we are applying a Bible passage to our lives in the right way? One way we can check our application is to see if it lines up with the overall crux of the book. If it fits with the main point that the author is making, there is a good chance that it is a good application. But if it is completely off the crux of the book, we likely have understood some verses incorrectly.

We might miss the main point of the entire book. Finally, if we do not first work on finding the main point of a book by putting the crux tool to work, we may discover that we have worked through a book passage by passage and missed the book’s big idea. That would not be a good thing. Putting the crux tool to work first can help us get a big picture of the main point of the book. Then, as we work through it passage by passage, we can see the way each individual passage relates to the overall big idea that the author is trying to communicate.

Every author of the Bible was inspired by God’s Holy Spirit to write, and they wrote with a very clear purpose—a big idea.

Benefits Received with This Tool

Now let’s think about some benefits that can come from using the crux tool well.

Hearing the main “melody” of the book. In musical pieces, there is almost always a main melody that is repeated throughout. There are pieces of harmony that are combined with this melody, but the melody serves as the main musical theme for the entire piece. Books of the Bible can be much like this. There are often many elements of harmony that combine with the main theme, and there are different variations of the big idea that the author is trying to get across. But ultimately there is one main melody that the book really centers on—its main message. The crux tool is ideal for helping Bible students find their way to that main melody so that they will keep their focus on the main point of the biblical author.

​​Understanding the author’s intention. The above point leads us to a second important benefit of the crux tool. When this tool is used well in a book of the Bible, the Bible student can actually see the main intention of the biblical author. He or she can begin to discern what the author is trying to do in different parts of the biblical book. This is the best way to “get inside the heads” of the writers of Scripture, to see their books from their perspective. Also, as we learned previously in connection with the context tool, finding the intention of the original author—and the perspective of the original audience—is key to making sure that we get our interpretation and application of Scripture right.

Connecting individual passages. Perhaps the greatest benefit of using the crux tool well is that, when the big idea of a book is located, it helps you connect the biblical passages in the book to one another because you can see how they are all relating to—or expanding on—the overall theme of the book. Passages in a biblical book change from being random stories, arguments, or poems to being important pieces in the overall point that the book is making for its audience. In other words, the crux tool can help bring a good, grounded perspective on every part of the book, which will help you in your study of each individual section.

This article is adapted from ​​Understanding God’s Word: An Introduction to Interpreting the Bible by Jon Nielson.



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