Christian Theology: Books, Subjects, Summary, and More Info

Theology is a compound word that means “the study of God.” Every religion has some type of theological system that guides it, and generally, sacred texts support those religious beliefs. The Bible is the sacred text used for theological development in Christianity. However, Christian Theology is different than every other theological system due to its unique claims about the Bible, Jesus Christ, and God.

Millard Erickson, a Christian theologian, offers a simple but eye-opening definition of Christian Theology. He characterizes it as examining, interpreting, and organizing the Bible’s information in an attempt to believe what Jesus Christ also believed.1

In other words, Christian Theology should be understood as an umbrella term for the overall collection of knowledge about God that is produced by reputable Christian theologians, developed from biblical principles, and compatible with the teachings of Jesus Christ.

Collectively, Christian theologians have produced numerous publications in an attempt to document, elaborate, or revise various doctrines about God. Through their continued efforts, they help refine and advance our knowledge of God through theology. However, although that endeavor is perpetually ongoing, the unanimously accepted doctrines about God within Christian Theology were established long ago.

Nevertheless, whether old or new, every doctrinal insight holds a degree of importance. Consequently, in order to classify them, the totality of theological knowledge within Christianity is organized into four categories. The following four fields of study combine to provide a significantly comprehensive understanding of Christian Theology: Biblical Theology, Historical Theology, Systematic Theology, and Practical Theology.

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Helpful Books about Christian Theology

There are plenty of Christian Theology books out there, but it’s a real challenge to find the books that are good. When evaluating the merits of a good theology book, it’s extremely important to ensure the quality of the content. However, that’s a difficult task if you’re new to Christianity or have just recently started learning about theology. So, whether you’re new to the faith or new to theology, we all need a little help at first. That’s why we’ve taken the opportunity to curate and recommend a trustworthy selection of Christian Theology books.

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Christian Theology, 3rd Edition

Dust jacket of the book, Christian Theology.
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Millard J. Erickson’s book, Christian Theology, is a widely used and respected overview of the core doctrines in Christianity. In fact, prominent Christian universities and seminaries across the United States use it as their textbook for theology curriculums. However, contrary to what you’re probably thinking, this book isn’t just for students or academic theologians.

Instead, the book takes a holistic approach to Christian doctrine by presenting a broad range of theological positions and possibilities. It surveys the different perspectives of Christian theologians, including Erickson’s own also. Consequently, the book simultaneously educates readers and encourages them to choose the position that makes the most sense.

Erickson covers a broad range of theological concepts but systematically presents them in a logical, coherent, and readable way. His writing is concise but clear, and he makes it easy for readers to grasp differing theological ideas. As a result, this book is a treasure for anyone serious about theology. This book is perfect for learning the spectrum of theological positions within Christianity as well as evaluating the merits of each one.

Why It's #1

Erickson doesn’t explicitly tell you what to believe in Christian Theology. Instead, when writing about the credibility of different theological positions, he evaluates the probability of what’s most likely. Erickson’s temperate and humble approach to theology is both graceful and admirable.

Exploring Christian Theology: Creation, Fall, and Salvation

Dust jacket of the book, Exploring Christian Theology.
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Exploring Christian Theology: Creation, Fall, and Salvation is the second volume in a trilogy edited by Nathan D. Holsteen and Michael J. Svigel. We highly recommend reading all three volumes, but if you can only choose one, this is the book to get. If you’re looking for an introduction to the basics of Christianity, it’s undeniably the best book in the trilogy for that.

Like the title suggests, this book is a broad survey of three theologically robust doctrines from the Bible. It explores creationism through different lenses of intelligent design and humanity’s fall from grace due to Original Sin as well as God’s salvific response to that sinful dilemma through Jesus Christ. These three subjects are essential to Christianity and certainly some of the weightiest in all of Christian Theology.

Holsteen’s and Svigel’s editorial handiwork makes the book an easy read without sacrificing scholarly depth. They make complex theological ideas understandable and provide numerous practical applications for the reader to consider. Their balanced approach to this theology book expertly integrates the disciplines of Biblical Theology, Historical Theology, Systematic Theology, and Practical Theology.

Christian Theology: Biblical, Historical, and Systematic

Dust jacket of the book, Christian Theology: Biblical, Historical, and Systematic.
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Adam Harwood’s book, Christian Theology: Biblical, Historical, and Systematic, provides an extensive analysis of Christian beliefs and doctrines. His treatment of these issues is comprehensive and also multidisciplinary. As the subtitle notes, Harwood explicitly uses three theological fields of study to survey them: Biblical Theology, Historical Theology, and Systematic Theology.

Harwood uses each field of study to demonstrate the theological depth of these Christian beliefs in three ways. Firstly, he examines the biblical foundation for each theological idea. Secondly, he reviews the historical development of these ideas over the course of time by the Church. Thirdly, he systematically organizes and articulates the doctrines of Christianity in robust detail.

This book is a valuable resource for anyone interested in thoroughly understanding Christianity. It examines the most important doctrines of the faith through three primary lenses of theology. The book prioritizes the value of Scripture, reflects on church history, and utilizes theological systems.

The Significance of Christian Theology

It’s hard to overstate the significance of Christian Theology or overestimate its impact on the world. The prevailing theological beliefs of a civilization influence almost every aspect of that society in one way or another. Theology holds the power to affect our thoughts, decisions, actions, and outcomes. However, unlike other religions, Christianity encourages us to navigate our religious worldview and theological beliefs in light of its claims about Jesus Christ.

Who is Jesus Christ to you? The answer to that question is multifaceted and varies from person to person, but it’s inescapably related to Christian Theology. Whatever our answer, we all come to our conclusions about Jesus Christ through doing some measure of theologizingTherefore, to a certain extent, everyone who answers this question is performing the role of a theologian. 

Christian Theology is the backbone of Christianity and unyieldingly asserts that faith in Jesus Christ is the only way to have a right relationship with God.

The truthfulness of that Christian assertion is of utmost significance and makes Christian Theology relevant for every person in the world. Christianity affirms that your belief or disbelief in Jesus Christ will forever shape your spiritual destiny. Belief results in eternal life and heavenly unification with God, but disbelief results in eternal death and hellish separation from God. Therefore, as you engage in the study of God, it’s important to learn what Jesus said about himself because his claims are fatefully significant.

Fields of Study in Christian Theology

The totality of Christian Theology is able to be organized into four primary sections. Each section contains the subjects and topics related to that particular category of knowledge. Collectively, these categories help catalog and reference the varying beliefs and ideas that are held throughout Christianity. However, although they are different branches of knowledge, there is an overlapping network of interconnectivity and applicability between their subjects and insights. Every theological issue can be classified into one of the following four fields of study: Biblical Theology, Historical Theology, Systematic Theology, and Practical Theology.

Biblical Theology

Theologian Bryan Rosner provides us with a succinct but sturdy definition of Biblical Theology. At first, he simply describes it as “the overall theological message of the whole Bible.” However, he later expands upon that description with some conditions for discerning that overall message. Firstly, the interpretative process must be overseen by the Church in general. Secondly, biblical theologians must consider the historical and literary contexts. Lastly, this field of study should maintain a Christocentric focus with regard to the overall narrative of the Scriptures.2

Essentially, Biblical Theology studies how the Bible interprets itself through the storyline. This field of study is focused on the unity of the Scriptures and the developmental connections between its books.

Accordingly, Biblical Theology is also sensitive to how the Scriptures would have been understood by their intended audiences. The theological symbols, significant geography, societal issues, familiar idioms, literary themes, and repeated patterns that were relevant to those ancient cultures are especially vital to biblical theologians because they provide a more accurate understanding of the Bible. As a result, the authorial intent of the Bible’s original authors becomes critical to the theological process of interpretation. 

The authors of Scripture contributed to a historical narrative that developed over millennia to encompasses many subjects. These subjects range in their significance, but most important, the Gospel is studied at length and revealed in detail. Biblical Theology invites us to understand how one subject is connected to another in Christian Theology.

Historical Theology

Historical Theology is focused on the lifespan of Christianity, explicitly noting its theologically significant people and events. Therefore, this discipline catalogs the teachings of Christian leaders and theologians who helped guide the Church throughout history. Consequently, it also traces the political shifts and theological splits that occurred over the course of time. These factors combine to paint a clearer picture of Christendom as well as its diversity of theological positions.

Theologian Gregg Allison did well in summing up the discipline of Historical Theology. He defined it as the study of how the Church has interpreted Scripture and formulated doctrine throughout history.3 However, that definition only scratches the surface of why we should value it.

Historical Theology identifies the significant differences between the theological beliefs of Catholic, Orthodox, and Protestant Christians.

However, it also enshrines the ecumenical beliefs that unite all Christians together in unity under God. It proudly affirms orthodox beliefs and doesn’t shy away from acknowledging the heretical beliefs that emerged also. Nevertheless, the dogmas and doctrines that permeate the different branches of Christendom are all rooted in Historical Theology.

This field of study helps explain the overall condition of Christianity. It exists as a historical record of significant events and a theological proving ground for doctrines. It presents an unvarnished history of Christianity so that we learn from the insights, whether old or new. Historical Theology is a map for Christian Theology that charts how we got here, wherever here may be for you.

Systematic Theology

Systematic Theology synthesizes all of the biblical information about a subject then presents those findings in an orderly manner. Theologian Wayne Grudem suggests that it’s best characterized as learning what the entirety of the Bible teaches us about any topic. In other words, it helps answer the following question: “What does the Bible say about [insert your subject here]?”4

Consequently, Systematic Theology topically catalogs its subjects and corresponding data. However, this field of study doesn’t randomly select its topics to pursue. Instead, it focuses on the ones that are impacted by the beliefs and doctrines of Christianity. Furthermore, it provides a framework for understanding and responding to theological issues that society is currently facing. 

Systematic Theology combines insights from Biblical Theology and Historical Theology to produce equally important theological knowledge for us today.

Coupled with the other disciplines, Systematic Theology helps us accurately apply biblical principles to our modern questions. Accordingly, to help categorize that information, it houses multiple branches of knowledge. Doctrines and insights fit into one of the following categories of theological study: Theology Proper and/or Paterology, Christology, Pneumatology, Soteriology, Bibliology, Ecclesiology, Eschatology, Angelology, Demonology, and Hamartiology. 

Systematic Theology provides a rational basis for belief in two notable ways. Firstly, it methodically organizes and sensibly explains the theological doctrines within Christianity. Secondly, it continually seeks to provide a biblically informed perspective for our modern issues and social controversies. It’s a remarkably relevant discipline and, presently, the most popular in all of Christian Theology.

Practical Theology

Practical Theology is best understood as a multifaceted field of study with communal and personal applications. It fixates on the best methods and techniques for faithfully living out the Christian worldview. However, depending on their perspective, theologians tend to prefer or emphasize one approach above another.

Pete Ward is a theologian who recognizes that Practical Theology is a holistic discipline overall. Therefore, he broadly defines it as operating with a mentality that treats the intersection of theology and practice seriously. Additionally, he considers prayer and worship to be fundamental and necessary for regularly encountering God in this process.5

Practical Theology helps answer an especially significant theological question: “As a Christian, how should my beliefs affect my actions?”

Generally speaking, Practical Theology focuses on how churches and Christians should incorporate theological beliefs into their practices and lifestyles. The combination of these dynamics produces a range of parameters and possibilities for Christian living and Church practices. 

Practical Theology is an unquestionably essential part of Christian Theology. It’s analogous to the wheels of a vehicle because Christianity is immobile and ineffective without it. In other words, this field of study drives us forward with ways to apply what we believe.

Summary of Christian Theology

Christian Theology is an overarching label for the many collections of theological doctrines and spiritual beliefs across Christendom. These insights are due to and developed from the reputable study of God by Christian theologians. As a result of the vast theological knowledge within it, Christian Theology can be organized into four different but interconnected fields of study: Biblical Theology, Historical Theology, Systematic Theology, and Practical Theology

The beliefs and teachings within Christianity are formulated from the insights produced by those fields of study. Therefore, Christianity does not exist without Christian Theology! 

Consequently, each field of study within Christian Theology is meaningful and significant. Biblical Theology helps us interpret the Scriptures as well as understand the storyline of the Bible. Historical Theology helps us understand the history of the Church and also records the important ideas, influential people, and significant events that shaped the course of Christianity. Systematic Theology helps us comprehend and explain the doctrines of Christianity as well as answer modern questions about contemporary issues of a theological nature. Practical Theology helps us put our faith into practice and also consider how our beliefs should affect our actions. 

These four fields of study can be further dissected into even more theological subcategories. However, every subcategory fits back into one of those four categories. Although there are many theological doctrines and beliefs that shape the religion of Christianity, anything you want to learn about Christian Theology fits into one of four fields of study.

FAQs Answered by Christian Theology

God is a singular being consisting of three separate and distinct but equally divine persons: God the Father, God the Son, and God the Holy Spirit. 

In Christianity, these three persons are collectively referred to as the Trinity. Each of them has a unique role and function within the Godhead. They comprise the eternally self-existent God of the Bible named YHWH or YHVH (Yahweh, Yehovah, Jehovah, and other possible pronunciations).

Jesus Christ is the second person of the Trinity (God the Son). In Hebrew, the name Jesus means “salvation” or “God will save,” and it was bestowed to prophetically outline the purpose of Christ’s life on earth. However, not to be confused with a surname, Christ is a Greek rendering of a theologically Jewish title (Messiah) meaning “anointed one” and reserved for the coming king of Israel. In the Bible, Jesus Christ is recorded to have died by crucifixion, been buried for three days, and resurrected from death on a Sunday. Now, after having conquered death and ascended to heaven, Jesus is presented as being the head of the Church, the savior of Christians, and the only one able to freely give eternal life to those who faithfully follow him as king of their lives.

Salvation is a process that can be dissected into three parts: justification, sanctification, and glorification. 

These three parts are phases of increasing spiritual development. Justification is starting point of salvation that comes from repenting of your sins, believing the Gospel about Jesus Christ, and confessing that belief through word (testimony) and deed (baptism). Sanctification is the middle phase of salvation that continues over the course of your life after receiving the Holy Spirit who labors to purge you of sinfulness, grow you in spiritual maturity, and conform you to be more like Jesus Christ. Glorification is the final stage of salvation that comes when we are permanently united with God after our death and subsequent resurrection.

The Holy Spirit is the third person of the Trinity (God the Holy Spirit). He is a disembodied spirit sent by God the Father to indwell believers after their repentance from sin and acceptance of Jesus Christ as Savior. His indwelling brings both comfort and help for Christians as they follow their king, Jesus Christ. The Holy Spirit comforts believers in times of distress and persecution, and he helps believers grow in their process of sanctification, remember the teachings of the Bible, and discern the will of God in their lives.

People can communicate with God through prayer, and typically, God answers our prayers in a few different ways. However, the presence of sin in your life can hinder your prayers (Isaiah 59:2). The book of James teaches that the motives behind your prayer is another factor considered by God (James 4:3-4), but it also affirms that the prayers of a righteous person are powerful and effective (James 5:16). We strongly suggest that you repent of sins and examine your motives before approaching God in prayer.

Initially, God wills for you to be in a right relationship with him. This is only possible through accepting Jesus Christ as your personal savior and making him the king of your life. After this intensely heartfelt process that results in a spiritual rebirth, God will incrementally reveal his plan for your life as you grow in relationship together and empower you to complete it through the continual help of the Holy Spirit.

The Bible, divided into the Old and New Testaments, is the sacred text of Christianity. It starts in the Old Testament with the creation of the world and humanity, followed by the history of the Israelite people, God’s covenant(s) with them, their common struggle with sin and evil, and the promise of a coming Messiah. The Old Testament ends without the Messiah being revealed, but the New Testament opens by introducing this figure as Jesus Christ and continues by telling the supernatural story of his life. His unique theological teachings, sinless life, substitutionary death, and subsequent resurrection form the foundations of Christianity. The Bible concludes by recording the growth of the early Christian Church and the promise of Christ’s return thereby framing the story of God’s creation, Christ’s redemption, and their ongoing relationship with humanity through the Holy Spirit.

The book of Hebrews instructs Christians to not neglect or abandon the church (Hebrews 10:25). 

However, it might surprise you to learn that a “church” is not a building or a location but a group of Christians gathered together. Nevertheless, Christians tend to gather in buildings, and although it is a misnomer, the building itself is often referred to as the “church” in time. Therefore, the point of church is gathering with other Christians to worship God as a group in unison, hear and read the Bible together, disciple those new to the faith, mutually maintain spiritual accountability, and encourage each other to live expectantly as the Day of the Lord grows closer!

The Bible describes the fate of every human after death with two possibilities that are presented as eternal destinations: hell or heaven. 

These two locations are radically different. Hell is depicted as a place of fiery torment, full of weeping, devoid of goodness, the prison prepared for Satan, and the destination of unfaithful people who have rejected God. On the other hand, heaven is depicted as a place of colorful beauty, full of joy, filled with the radiance of God, and the destination of faithful Christians. Hell is ultimately described as a realm that’s fearfully absent of God’s presence and inhospitable to life, but heaven is ultimately described as abundantly filled with all kinds of life and a realm that’s permeated with love from the abiding presence of God in it.

No singular answer is satisfactory. Instead, like a mosaic, an explanation for the problem of evil is best presented through multiple theodicies. A theodicy is a vindication of God’s goodness in light of the existence of evil in the world. No theodicy is adequate explanation for evil on its own, but when considered altogether, a multifaceted explanation for the presence of evil is revealedEach theodicy is like a piece of the puzzle that rationally explains why God currently allows evil to exist. Nevertheless, there is a day coming when God will tolerate evil no more and forever rid the world of it.

  1. Millard J. Erickson, Christian Theology, 3rd ed. (Grand Rapids, MI: Baker Academic, 2013) 6-7.
  2. B. S. Rosner, “Biblical Theology,” in New Dictionary of Biblical Theology, eds. T. Desmond Alexander and Brian S. Rosner, (Downers Grove, IL: InterVarsity Press, 2000), 3-10.
  3. Gregg R. Allison, Historical Theology: An Introduction to Christian Doctrine (Grand Rapids, MI: Zondervan Academic, 2011), 23.
  4. Wayne A. Grudem, Systematic Theology: An Introduction to Biblical Doctrine (Grand Rapids, MI: Zondervan Academic, 2000), 21.
  5. Pete Ward, Introducing Practical Theology : Mission, Ministry, and the Life of the Church (Grand Rapids, MI: Baker Academic, 2017), 9-10.