Systematic theology might sound like a topic better left for the pros—those pastors and teachers called by God to do the heavy lifting for us. We trust them to sift through the words, topics, and themes in the Bible, tie everything together, and present it to us in a way that’s easy to digest.
And the average Christian’s posture toward God and the study of Scripture seems to reflect this. A recent LifeWay study revealed that only 32% of Christians read their Bible every day, and 12% said they rarely read it,1 if ever. And that’s reading the Word, not studying it.
Yet Scripture calls all believers to search the Scriptures (Acts 17:11) and rightly handle the word of truth (2 Tim 2:15).
One way to do this is through what’s called “systematic theology.” Those two words might sound intimidating, but when broken down, systematic theology is really quite simple—and it could dramatically change your perspective of how perfectly God has knitted together his Word from beginning to end.
What is systematic theology?
Let’s first define theology. The word “theology” comes from two words: theos, meaning “God,” and logos, meaning “word” or “discourse”—thus, discourse about God.2
There are several types of theologies, and each has its purpose and place in the study of God:
- Biblical theology identifies distinctive themes in various sections of the Bible, like the Old Testament or Paul’s writings, and traces them from one section to another to discover unifying themes that tie the whole Bible together.3
- Historical theology is the study of theology’s unfolding throughout the centuries and how Christians have understood theological topics in different periods.4
- Practical theology (sometimes called applied theology) studies theology in a way that makes it useful or applicable to everyday life. It deals with preaching, teaching, evangelism, church planting, missions, and the like.5
But systematic theology is unique. It centers on studying the entire scope of the Bible to gather everything Scripture teaches about a particular topic or issue. Systematic theology involves “collecting, scientifically arranging, comparing, exhibiting, and defending . . . facts from any and every source concerning God and his words”6in a carefully organized way7and then making a claim on that data. It combines interpretation to discern the meaning of Scripture with biblical theology to process the historical-redemptive process of particular themes—but also leans on historical theology to “perceive how elements of truth have become formulated and later developed.”8
Think of it this way. You could study the book of Daniel’s teaching on the end times in the context of the entire Bible—this is biblical theology. Or you could study how people in a different time period understood end times, which is historical theology. Applying the Bible’s teaching on the end times to everyday life falls under practical theology.
But taking that same topic, end times, and systematically sifting through everything Scripture says about it from the beginning of Genesis to the last pages of Revelation and also considering church history, philosophy, and life application9—that’s systematic theology.
Areas of systematic theology
Systematic theology is broken down into several categories or “doctrines”10—what the whole Bible teaches about a particular topic. Andrew Naselli, assistant professor of New Testament and biblical theology at Bethlehem College and Seminary, suggests 10 doctrines that are the “big headings under which most systematic theology fits”11:
- Theology proper (the doctrine of God)
- Bibliology (the doctrine of the Bible)
- Angelology (the doctrine of angels and demons)
- Anthropology (the doctrine of humanity)
- Hamartiology (the doctrine of sin)
- Christology (the doctrine of Christ)
- Soteriology (the doctrine of salvation)
- Pneumatology (the doctrine of the Holy Spirit)
- Ecclesiology (the doctrine of the church)
- Eschatology (the doctrine of the end times)
Each is a key doctrine in the history of the church and important for believers over all time, and most have many subcategories. For example, Christology covers Jesus’ birth, life, death, resurrection, and ascension, as well as his deity, humanity, all the Old Testament prophecies about him, and his return to earth and reign. It answers some of the big questions about Jesus, like Is Jesus God? and How can Jesus be both God and man?
Studying each doctrine is like one piece of a jigsaw puzzle that helps to complete a beautiful picture. As you better understand each doctrine and put it together with the rest, it begins to give you a more complete picture of God and his perfect plan of redemption.
Why should Christians study systematic theology?
In his acclaimed work Systematic Theology, Wayne Grudem offers several reasons Christians should study systematic theology—but says the most basic is that Jesus commands it.12 Just before ascending to heaven Jesus instructed his disciples (and now us) to:
Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you; and lo, I am with you always, to the close of the age. (Matt. 28:19–20, emphasis mine)
To teach all that Jesus commanded means “to teach the content of the oral teaching of Jesus as it is recorded in the gospel narratives.”13 However, in a broader sense, Grudem says:
“All that Jesus commanded” includes the interpretation and application of his life and teachings, because in the book of Acts, it is implied that it contains a narrative of what Jesus continued to do and teach through the apostles after his resurrection (note that [Acts] 1:1 speaks of “all that Jesus began to do and teach”). Thus in a larger sense, “all that Jesus commanded” includes all of the New Testament.
Furthermore, when we consider that the New Testament writings endorse the absolute confidence Jesus had in the authority and reliability of the Old Testament Scriptures as God’s words (see chapter 4), and when we realize that the New Testament epistles also endorse this view of the Old Testament as absolutely authoritative words of God, then it becomes evident that we cannot teach “all that Jesus commanded” without including all of the Old Testament (rightly understood in the various ways in which it applies to the new covenant age in the history of redemption) as well.14
And for Grudem, the best way to teach ourselves and others what the whole Bible says is to do so systematically—by gathering and organizing all Scripture passages on particular biblical topics.
Is systematic theology beneficial?
You might be thinking, Is there a practical reason to study the Bible this way? Grudem says yes and offers three benefits for studying systematic theology:
- It helps guard us against imposing our ideas on Scripture. Because we’re human (and sinners), we’re apt to find some biblical teachings hard to embrace. The study of systematic theology helps us overcome wayward ideas about God, the world he created, and his law that ought to govern our lives.
- It helps us answer questions that arise over future doctrinal controversies. There’s no way to know what new doctrinal issues could surface in our lifetime.15But since the Bible is one large book in which every single part is somehow related to the whole, learning systematic theology will equip us to handle those new questions better.
- It helps us mature in our relationship with God. The more we know about God and his Word, the more we will experience his faithfulness, and the more we will trust and obey him. This is the “knowledge of the truth that leads to godliness” Paul wrote about in Titus 1:1.16
How to start studying systematic theology
Studying systematic theology isn’t only for seminary students. In fact, if you’ve ever told someone, “Scripture says the Holy Spirit is . . .” you’re applying it already—you just might not have known it.
If this is a new step for you, we suggest starting with these ideas.
1. Tap into systematic theology resources
You can start by picking up a resource like the ESV Systematic Theology Study Bible. Or you might explore one category of systematic theology—like soteriology in Sojourners and Strangers: The Doctrine of the Church or pneumatology in He Who Gives Life: The Doctrine of the Holy Spirit.
To study systematic theology more in-depth, consider a resource like Wayne Grudem’s Systematic Theology, Second Edition, what Tim Challies calls “an ideal textbook” for its “lucidity and simplicity.” (Tip: There’s still time to pre-order this revised and highly sought-after systematic theology at a discount.) It’s suitable for any believer, whether you’re a longtime systematic theology fan or just beginning to dabble in it.
Or you could take a Logos Mobile Ed course on a particular doctrine of interest with trusted scholars, like Christology: Prominent Titles for Jesus, or this one on different perspectives on the doctrine of eschatology.
Other great systematic theology books include Louis Berkhof’s succinct, clear, and well-organized Systematic Theology. Or for a more exhaustive treatment of the subject, consider Normal L. Geisler’s Systematic Theology (4 vols.).
Charles Hodge’s Systematic Theology (3 vols.) is noted for its clear writing and thorough scholarship from a Reformed tradition. And Systematic Theology: An Introduction to Christian Belief by John Frame shows how the Bible explains God’s sweeping plan for mankind with clear and practical language accessible for both pastor and layperson.
2. Use Bible software
Today, we’ve got technology at our fingertips that makes the study of systematic theology easy. (And the people rejoiced!) For example, the Passage Guide in Logos Bible Software17 shows you everywhere systematic theology resources in your Logos library reference a biblical passage and then filters the results by subdiscipline and even denominational affiliation.
See how it works:
For just a little while longer, save 20% when you pre-order Wayne Grudem’s Systematic Theology, An Introduction to Biblical Doctrine, Second Edition, the most widely used resource in its field.
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