Theology is like a wedding cake. And when done well, it is scrumptious and delicious. It's like a lovely four-tiered wedding cake. Oh, and it has a grooms cake on the side.
Believe it or not this is actually somewhat of a serious illustration. Because there at least five different types of theologies that we can be talking about when we talk about "theology." Most of the time we use the word "theology" in a fairly undifferentiated sense, and most of the time that works out just fine, but occasionally it is nice to be precise. There are five different things we are sometimes talking about when we discuss theology. Four of these stack one on top of the other, in the manner of a wedding cake, the fifth is related but separate, we'll call it the grooms cake.
Much like a four tier cake, it is essential that the layers are stacked in the correct order. You can imagine the disaster that would result if one put the smallest layer on the bottom, or the biggest on top. The bottom layer is foundational for the one above it, and the second layer in turn, is foundational for the layer on top of that one, etc. A visual aid would be nice here, but my art skills are pretty limited, so use your imagination.
The first (and foundational) layer is
Exegetical Theology. Exegetical theology is what we are doing when we are talking about the meaning of specific verses, chapters, and books in the bible. When we discuss the literary context, the meaning of the Greek and Hebrew, the flow of the argument, and so on. This is the foundation of all theology. So long as we want our theology to be based on the Bible, we need to discuss what particular parts of the Bible mean. The rest of the theological cake rests on this.
The second layer is
Biblical Theology. To engage is Biblical Theology, is to think about all the different parts of the bible, and put them together into a meaningful whole. It helps, in this regard, to remember that the Bible is a story with a plot, it has a trajectory. So when we think biblically-theologically about, say, the temple, we are not thinking about individual verses (although we need to have done that first!), we are thinking about the way the tabernacle was revealed on Mt. Sinai as a reflection of the garden of Eden, traveled through the wilderness, morphed into the Temple, was destroyed by Babylon, rebuilt by Zerubbabel, and replaced by Christ. Notice how was attempting to follow the biblical storyline, and to see and appreciate the twists and turns of the story, and effect of progressive revelation.
The third layer of the theological cake is
Systematic Theology. Systematic theology as a discipline is now attempting to gather together everything we know from the bible about a particular topic and make a coherent sense of it. Again, this type of theology might not deal in detail with passages from the Bible, because it is assuming that that work has already been done.
The fourth and final layer of the cake is
Practical Theology, also sometimes called Pastoral Theology, but it is practiced by all of us, not just pastors. All of us often engage in practical theology. It is what we are doing when we ask the question "How should we then live?" Once we have examined the biblical texts, become aware of the way the topic functions throughout the bible, and gathered all our knowledge together, then we are ready to put it into practice.
These four tiers are all important, and the order of them can not be changed, reversed or ignored, except to our own theological peril. But there is one more way we often talk about theology, and that is
Historical Theology. This is what we are doing when we investigate when John Calvin thought about a particular issue, or how the Puritans viewed such-and-so. I consider this to be the grooms cake, because it is important, but not integrally related to the other four disciplines.
Perhaps an example would be helpful here. Say we are trying to think theologically about the Sabbath and its importance for the church today. We start at the bottom of the cake, by asking what does the Bible say about the Sabbath. So we carefully investigate Genesis 1-2, Exodus 16, 20, 31, Deut 5, Isaiah 58, Mark 2, John 5, Romans 14, Col 2, Heb 4, etc. This is the practice of
Exegetical Theology. Next, we would step back and look at the trajectory. Was Sabbath observance of different importance at different periods of the covenant families life? How was it progressively revealed to Israel, and has the inauguration of the New Covenant changed how we think about it? This is
Biblical Theology. The third step is to gather all our information together, and see what we can say from a
systematic standpoint. Only after we have done all of these steps, are we in a position to ask how we are to live now? What should we do on Sunday afternoon? In other words, we can now pursue the task of relating the Bible to life, or doing
Practical Theology.
And if you are still hungry, there is no reason to neglect the grooms cake, asking how different theologians throughout
history have viewed the issue. This can be both interesting and informative, but we should remember to read with a discerning eye. Just because John Calvin wrote it, doesn't make it more sure than the Bible!
Let me explain why this cake is important. No one on earth is equally skilled at doing all five layers of theology, we all tend towards one or two, and are weaker in the others. Most pastors I know really excel at the top two tiers (systematics and practical), and of course, in order to be a pastor you need to know how to help people apply the Bible to their lives. But these pastors need to be humble in recognizing that they need help with the exegetical task, which is foundational to the whole enterprise. There are some pastors who really excel at exegesis, who love to read commentaries, who still know Greek and Hebrew five years after seminary. This is great because it is foundational, but they often need help in making practical application of the truths they discover to the lives of their parishioners.
It has been helpful to me when I read a particular theological piece to ask where it fits into the whole theological cake, what is supporting it, and what could potentially be the next step? Not all theology is done the same way. And the point of this exercise is not to say that one layer is the most important of all, but to say that
it is absolutely vital that we have the whole cake!