“No one believes more strongly than I do that every Christian should be a theologian. In that sense, we all need to work it out. I want all Christians who can read, to read their Bibles and to read beyond the Bible - to read the history and theology.”
- D.A. Carson
The Bible wasn’t written in systematic fashion. It isn’t a dictionary of theological concepts nor does it present us with any kind of taxonomy of its doctrines. The Bible is mainly a historical narrative—one continuous story from beginning to end. The theology of Scripture comes out of that redemptive story. Even the sections that aren’t overtly historical (e.g. the Psalms, Prophets, Epistles) constantly draw upon the historical narrative foundations of Scripture. But how do we go about organizing and classifying the doctrines spread so widely across redemptive history?
This is where Systematic Theology comes in. Systematic Theology is the attempt to categorize and summarize all that the Bible says on various meta topics, such as: God, mankind, salvation, and the end times. After categorizing and summarizing the biblical texts, the systematic theologian attempts to integrate extra-biblical disciplines such as historical, biblical, and philosophical theology. The goal here is an interdisciplinary conversation, beginning with the text of Scripture as Holy writ, and incorporating the insights of God’s other infallible witness of his divine attributes—nature. Thus, the Systematic Theologian seeks a dialogue between the “two books” of God—his natural and special revelation.
Biblical Theology differs from Systematic Theology in that it tends to be more inductive, seeking to understand an individual book of the Bible in terms of its own content, context, and cultural background. The biblical theologian seeks to describe and explain Scripture in terms of the human authors’ own cultural horizons, thought worlds, and meaning systems. Arguably, no theologian can divorce themselves from any other discipline and it is best to see these disciplines as complimentary and necessarily integrated.
Jesus is Christianity’s first practical theologian. In the parable of the foolish and wise builders (Mt. 7) Jesus contrasts two types of “builders”—the fool and the wise man. While the fool picked the choicest beachfront property on which to build, the wise man dug deep, found solid rock and constructed a sturdy home. Eventually the quality of each man’s work was tested. The home built foolishly on the shallow and shifting sand “fell with a great crash” while the wisely built home withstood the wind and flash floods. Jesus’ point? Don’t be like that fool. Instead, build your life on the bedrock of Jesus’ teaching. The wise man, according to Jesus, is the disciple who “puts my teachings into practice.” Practical Theology is the discipline of seeking to apply biblical teaching and theology to the Christian life.