This is an excerpt from Knowing God’s Truth, which won the Award of Merit in the Young Adult category of CT’s 2024 Book Awards.

Probably the biggest critique of the discipline of theology, even by Christians, is that it is not practical.

It is not surprising that people who do not know Jesus do not want to study theology. What is often quite disappointing is that many Christians look at theology as something that is not useful—something that does not really matter in everyday life. Perhaps you have not heard this yet, but you will!

There is a very real sentiment from some Christians that careful theological thought and study is a waste of time; Christians, these people think, should be out helping people, preaching the gospel, and engaging in active obedience rather than learning about God and the Bible.

So why is theology important? Why give many hours to its study?

The most basic reason why theology is important is that it is about God; it is the study of our Creator, Savior, and King. In a very real sense, then, the study of theology is the best and most important study that we can ever engage in.

It is not a waste of time to learn more about the God of the universe. It is, in fact, probably the most valuable thing we could be giving our time to do. The study of theology, of course, should not prevent us from helping people, sharing the gospel, and actively obeying Jesus; it should actually help us do these activities with even more knowledge of and love for God—and for human beings created by this God.

Theology also affects the way we live. Many people do not realize that every decision we make is ultimately a theological decision. Everything we do is a reflection of our beliefs—especially our beliefs about God. What we say, how we think, the way we use our time—all of these ultimately reflect what we truly believe to be true about the universe and the meaning of life. In this sense, then, our theology really does affect the way we live. What we believe about God has an impact on the choices we make—even the small ones—every single day.

Finally, a theological view of the world that is informed by the Bible helps us make sense of the world around us. God, in his Word, reveals to us the deepest realities about our world: his role in creation, the sinfulness of humanity, his sovereign purpose and plan, and the salvation that is available only through Christ Jesus, his Son. Careful theological work, then, matters because it is a way for us to understand and make sense of the world.

Article continues below

When we study theology, we come to see our purpose as we understand God’s role in the world by listening his Word. Systematic theology begins with a study of the doctrine of Scripture because without God’s revelation, we cannot know about God. But why not start by examining God’s existence, character, and actions, since God obviously has been around (infinitely) longer than the Bible?

We begin with Scripture because we are weak, finite creatures who cannot simply rely on reason and careful thought to lead us to the truth about the God of the universe. Certainly we could come up with some good ideas about God, but we cannot even start down this road in the right way until we have laid a solid foundation for study, discussion, and thinking about him. Scripture is this foundation.

We can get to a certain point in our understanding of God without the Bible; we can see that he exists and that he is powerful. But we need his Word to show us the rest of what we can know of him—the rest of the truths about his character, his actions, and his way of salvation through his Son.

Our starting point is an examination of what the existence of Scripture itself tells us about the God who created this world: He is a God who speaks. This has important implications for the way that we approach Scripture. We come to it not as a “dead” book that we search for information, but as the living Word of God that has significant things to say about every area of our lives.

There is much that we can learn from the simple fact that God—the God of the Bible—speaks to people. When we refer to the Bible as the “Word” of God, we are saying that the one true God of the universe is a “speaking” God. He is not silent. He has not left human beings completely in the dark as to how they can know, love, worship, and serve him. He has spoken through his Word.

So what do we learn from the very existence of the Bible? First, we learn that the God of the universe wants to be known.

This is a key point for us to consider. The God who created us has gone out of his way to communicate with human beings. He reveals himself to them through his Word. He teaches them about his character, ways, and plan. He shows them how they can come into a right relationship with him. Our God speaks because he is committed to inviting people into relationship with him, so that they can actually know the God who created them!

Article continues below

Further, God wants to relate to his people through his Word. Throughout history, from God’s first words to Adam and Eve, we see that God’s primary way of relating to human beings is through his Word to them. He spoke to Abraham. He gave the Law to Moses. He spoke to his people through the prophets. His Son, Jesus, came as the “Word … made flesh,” according to John 1:14 (KJV).

Now, Scripture—his Word—guides Christians as they follow and relate to him. God’s Word is his primary way of relating to people. That’s why his people have always been people of his Word.

Finally, we learn from the existence of Scripture that we must listen to God’s Word. Since it is the communication and revelation of our Creator—the only true God of the universe—the Bible is the most important word we can listen to! We should work hard to listen to the Bible because the God who made us has actually spoken in it.

Here is what Paul writes about the Word of God:

All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work. (2 Tim. 3:16–17, ESV).

Paul’s phrase breathed out helps inform our understanding of inspiration. The Bible, according to Paul, is really “breathed out” by God. In other words, the Bible that we read and study is as closely tied to God as our words that we speak are tied to us!

How did God breathe out Scripture? He did it by the power of his Holy Spirit. This is what we mean when we speak of God inspiring human authors to write the books of the Bible. His Holy Spirit was actively and powerfully working in and through them as they wrote. Men such as Moses, Samuel, David, Paul, Peter, and John wrote with the inspiration of the Holy Spirit.

Now, we need to make a distinction between inspiration and dictation. Inspiration does not mean that God dictated every word to the biblical authors or somehow magically grabbed their hands and forced them to write certain words without their minds being engaged at all! The very nature of the Bible tells us this is not the case; it was written with distinct human personalities, styles, and tones that are representative of the authors.

Yet the truth of inspiration tells us that God’s Holy Spirit was powerfully overseeing each part of the writing of Scripture, so that as Paul wrote (from his own experience and with his own style), he was writing words and truths that completely and truly lined up with what God wanted to say to human beings.

Article continues below

One other passage that we should consider here comes from the apostle Peter’s second letter. Peter speaks of the prophets—who both wrote and spoke to God’s people—as being “carried along” by the Holy Spirit (2 Pet. 1:21). This is just one other picture that the Bible gives us for inspiration.

These men spoke and wrote by their own power, but they were “carried along” by the Spirit in a powerful way so that their words were perfectly united with his Word to his people—in just the way that he intended.

So what does inspiration mean when we talk about the Bible? It means that God is directly behind the words of Scripture. He sovereignly oversaw its composition by the power of his Holy Spirit. He “carried along” the biblical authors and “breathed out” his Word to us through their writing. Because of this, we can truly say that the Bible is God’s Word. We can say that when the Bible speaks, God speaks!

Because of the doctrine of inspiration, we can truly say that the Bible is God’s Word. We know that, in Scripture, we have a source of truth that comes directly from the sovereign God who powerfully inspired its words.

God did this through human authors, who wrote out of their own situations—and with their own styles and personalities. We can accurately say that the Bible is 100 percent human (written by human authors) and also 100 percent divine (inspired by God the Holy Spirit—every single word).

If there is one simple reality that we observe in every part of the Bible, it is this: God rules his people by his Word. To put it in a slightly different way, God’s Word is always attached to God’s authority—his rule over his people with power, protection, and strong instructions and commands. Indeed, whenever God speaks, he speaks with authority.

The doctrine of inspiration must necessarily lead into the doctrine of the authority of Scripture. If the Bible really is inspired by God—if it is “God speaking” by the power of his Holy Spirit—then the Bible is a book with great authority. It is the actual Word of God.

This means, quite simply, that there is no greater authoritative word in the entire world than the Bible. Because it is truly God’s Word, it is a word of authority and power; we must listen to it, respond in faith and obedience. The God of the universe has spoken; this is his authoritative Word, and we do well to listen and obey.

Jon Nielson is senior pastor of Christ Presbyterian Church of Wheaton in Wheaton, Illinois, and coeditor of Gospel-Centered Youth Ministry: A Practical Guide.

Content adapted from Knowing God’s Truth by Jon Nielson, ©2023. Used by permission of Crossway, a publishing ministry of Good News Publishers.

Have something to add about this? See something we missed? Share your feedback here.