Biblical Theology: Definitions and Distinctions
Prior to the Protestant Reformation, theological reflection was generally in the realm of what we would today call systematic theology. As can be seen by its name, the goal is to systematize or order the teaching of the Bible into a coherent expression of doctrine. One expression of this is in those rather large theology texts that seek to explain the Christian faith in a comprehensive fashion, covering its content under the standard doctrinal headings. But systematic theology can also be less broad and concern itself with looking at a particular doctrine, such as redemption. Systematic theology begins by observing what both the Old and New Testaments teach about it, with the aim of organizing all that material into a thorough and orderly explanation of the topic.
Biblical theology, however, is defined differently. With the Protestant Reformation came more of a distinction between biblical and systematic theology. Before we can organize Christian theology into a coherent body of doctrine, we need to look at it according to its biblical parts, as well as the biblical books that make up those parts. For example, if we want to seek to gain a proper understanding of the kingdom of God, using both the Old Testament and New Testament contributions, we must first look at what various biblical books tell us about it. So what do we learn about the kingdom of God from books such as I and II Samuel? Isaiah? Matthew, Mark, and Luke?
We also need to remember that while it is certainly true that all Scripture is inspired by God, such inspiration was carried out through many different human writers over a period of many centuries. So while there is indeed an organic unity to Scripture, it is also true that there is a rich variety as well. Thus, in order to discover the Bible’s unified tapestry concerning the kingdom of God, we need to consider each book on its own terms. For example, we need to understand each book’s particular historical context, literary style, vocabulary, and how it fits into the overall flow of redemptive history, centering in and pointing to the person and work of the Lord Jesus Christ. Once we have studied the relevant portions and books carefully, we can then broaden the topic to a biblical theology of the kingdom of God.
Once we do that, we start to move into the realm of systematic theology. But systematic theology will go beyond this, because it will also attempt to incorporate the contributions of historical theology so that we can see how our understanding of doctrine has developed throughout church history. As we study the Bible, we know perfectly well that we are not the first ones to have done so. By looking at the past centuries of theological reflection, we gain a deeper knowledge of Scripture as we see what other Christian thinkers have written about the Christian faith, as we, along with them, seek to increasing learn what it means to think God’s thoughts after him.