What is biblical theology? In once sense, all good disciplined theological reflection on the Bible could be called “biblical theology”. However, there is also the discipline of biblical theology. I think Elmer Martens described the discipline of biblical theology well;
Biblical theology attempts to embrace the message of the Bible and to arrive at an intelligible coherence of the whole despite the great diversity of the parts. Or, to put it another way: Biblical theology investigates the themes presented in Scripture and defines their inter-relationships. Biblical theology is an attempt to get to the theological heart of the Bible.
Now, let me explain why I believe that the discipline of biblical theology is of utmost importance. Most seminary students are required to complete courses in Old Testament, New Testament, and Systematic Theology. Many of these seminarians exit their studies with a good grasp of the two testaments on their own, and a good understanding of systematized theological subjects, but have a hard time putting it all together. To add to that problem, these seminarians graduate into pastoral ministry contexts and begin perpetuating a segmented understanding of the Bible throughout the Church.
I believe that the Bible is one unified story. I also believe that the Bible should be read as one unified story. This may seem like a daunting task. The Bible consists of sixty-six separate units, written over more than a thousand years against a wide variety of cultural backgrounds using different literary genres, by people who for the most part worked independently of each other. However, as J.I. Packer once noted, these “…books written centuries apart seem to have been designed for the express purpose of supplementing each other and illuminating each other.”
The beauty of biblical theology is that it explores the rich and multi-sided presentation of the unified message of the Bible, which centers on Jesus Christ. Personally, I think biblical theology is the key to bridging Old Testament studies, New Testament studies, and Systematic Theology. As D.A. Carson once wrote, ” [Biblical theology is] an excellent bridge discipline, building links among the associated disciplines and in certain respects holding them together.”