What Are We Even Talking About?

What Is Theology?

The word theology comes from two Greek words: theos (God) and logos (word, study, reason). Literally, theology is "the study of God." In practice, it is much more than an academic subject: the attempt to think carefully and faithfully about everything God has revealed about Himself and His relationship to the world.

Everyone is a theologian in some sense. The moment you have an opinion about who God is, what He is like, or what He expects, you are doing theology. The question is not whether you will have a theology, but whether your theology will be good or bad, careful or careless, rooted in Scripture or shaped by assumptions you have never examined.

Systematic Theology

This course focuses specifically on systematic theology: an approach that organizes Christian teaching into categories (doctrines) and examines what the whole Bible teaches about each one. Rather than reading through a single book of the Bible, systematic theology asks questions like: What does all of Scripture, taken together, teach about sin? About salvation? About the Holy Spirit?

Other approaches to theology include biblical theology (following the storyline and development of themes across the Bible), historical theology (tracing what the Church has believed throughout its history), and practical theology (applying doctrine to ministry and everyday life). This textbook will touch on all of these, but the organizing framework is systematic.

Why Does Doctrine Matter?

You may have heard someone say, "I don't care about doctrine, I just want to follow Jesus." This sounds humble and spiritual, but it contains a hidden problem: you cannot follow Jesus without having beliefs about who Jesus is. Every decision about how to live as a Christian is downstream from what you believe. Doctrine is the foundation of practical Christianity, not its opposite.

Consider the difference it makes to believe that Jesus rose bodily from the dead versus believing it was only a spiritual experience. Or the difference between believing God is personal and loving versus believing He is an impersonal cosmic force. These are not abstract puzzles. They change how you pray, how you grieve, how you make decisions, and what you hope for.

The Cost of Bad Theology

Bad theology does real damage. Throughout church history, distorted views of God, Christ, and salvation have led to spiritual abuse, moral failure, false assurance, hopelessness, and division. The Apostle Paul repeatedly warned that false teaching is dangerous, not merely inconvenient (Galatians 1:6–9, 1 Timothy 4:1–3, 2 Timothy 4:3–4).

This does not mean every theological question is equally urgent. Christians can disagree about many things while remaining united in the core gospel. But it does mean that clear, biblical thinking is never wasted. It is an act of faithfulness to God and love toward others.

Faith and Reason

A common assumption in our culture is that faith and reason are opposites, that believing in God is something you do when you run out of evidence, or when you prefer comfort over truth. This is a misunderstanding of both faith and reason.

In the Bible, faith is not blind belief in something you have no reason to accept. Faith is trust: trust in a person (God) based on His demonstrated character and reliable word. You exercise the same kind of faith when you sit in a chair: you have good reasons to believe it will hold you, and you trust it by sitting down. Biblical faith means taking God at His word and ordering your life accordingly.

The Role of Scripture

For Protestant and Baptist Christians, Scripture is the supreme authority for theology. This principle, often called sola Scriptura ("Scripture alone"), does not mean Christians ignore tradition, reason, or experience. It means that all of these are tested and normed by the Bible. When tradition contradicts Scripture, Scripture wins. When our feelings tell us something different from what God has revealed, we trust His word over our emotions.

This textbook will constantly return to Scripture. Doctrine that cannot be grounded in the Bible is human opinion, not Christian doctrine. As we study each doctrine, the most important question is always: What does God say?

The Nine Central Doctrines

This course is organized around nine core areas of Christian doctrine — sometimes called the "loci" (Latin for "places" or "topics") of systematic theology. Each one addresses a central question that the Christian faith must answer:

Bibliology: What is the Bible? Where did it come from, and why should we trust it?

Theology Proper: Who is God? What is He like? How do the Father, Son, and Spirit relate to each other?

Anthropology: What does it mean to be human? What is our origin, purpose, and design?

Hamartiology: What is sin? Where did it come from, and what has it done to us?

Christology: Who is Jesus? What did He do, and why does it matter?

Soteriology: How are sinners saved? What does it mean to be forgiven, justified, and transformed?

Pneumatology: Who is the Holy Spirit, and what does He do in the world and in believers?

Ecclesiology: What is the Church? What is its purpose, and how does it function?

Eschatology: Where is history going? What happens when we die, and what will God ultimately do with His creation?

Notice that these doctrines are interconnected — they tell one story. We begin with God because He is the starting point of everything. We end with eschatology because it is where His purposes are brought to completion. In between, we trace the story of creation, fall, redemption, and new creation.

Key Vocabulary

Key Scriptures

• 2 Timothy 2:15
• 2 Timothy 3:16–17
• Romans 12:2
• Proverbs 4:7
• John 8:32
• Galatians 1:6–9
• Colossians 2:8
• 1 Timothy 4:1–3
• Hebrews 11:1
• Isaiah 55:8–9