As the discussion in this meta answer reveals, defining theology (especially systematic theology) is challenging, and it varies by theologians. Consider this quote from Rolland McCune's Systematic Theology Volume 1, pages 3-4 (these are Christian, Protestant, mainly Reformed influenced theologians mentioned; obviously definitions could vary more with other traditions' influences; he does give footnote references for his sources):
Etymologically, theology comes from the Greek words theos (God) and logos (word), which suggest the “word concerning God” or “the study of God.” Systematic or Christian Theology then, in the widest sense, is simply doctrine—the doctrine(s) of the Bible set forth according to plan or order. Theology Proper is the subset of systematic theology that discusses the person and work of God.
Here a listing of other theologians’ definitions is helpful in giving a general sense of the scope of this discipline and a means of comparison and contrast with the definition given above.
- A. H. Strong: “Theology is the science of God and of the relations between God and the universe.”
- Charles Hodge: “Theology, therefore, is the exhibition of the facts of Scripture in their proper order and relation, with the principles or general truths involved in the facts themselves, and which pervade and harmonize the whole.”
- William G. T. Shedd: “Theology is a science that is concerned with both the infinite and the finite, with both God and the Universe. The material, therefore, which it includes is vaster than that of any other science. It is also the most necessary of all the sciences.”
- Lewis S. Chafer: “Systematic Theology may be defined as the collecting, scientifically arranging, comparing, exhibiting and defending of all facts from any and every source concerning God and His works.”
- James L. Garrett: “The ordered exposition of Christian doctrines.”
- Millard Erickson: “That discipline which strives to give a coherent statement of the doctrines of the Christian faith, based primarily upon the Scriptures, and related to issues of life.”
- Wayne Grudem: “[Theology is] any study that answers the question, ‘What does the whole Bible teach us today?’ about any given topic.”
- Robert L. Reymond: “[Systematic Theology] in its broad sense speaks of intellectual or rational discourse about God or things divine.”
- Stanley Grenz: “[Theology] is the believing community’s intellectual reflection on faith.”
Notice how they vary.
- Some refer more simply to doctrines (teachings) of the Bible systematized and ordered around topics
- Some mention general truths, the universe, or knowledge from other sources (I find this interesting, since even in doing exegesis, one is drawing on knowledge from "reality" or "experience" itself, so really any communication, including theological, is drawing from other sources)
- Some mention the generic term "Christian," though one can bet that their use is less "generic" than it needs to be for this site (and indeed cannot be used because of the inclusiveness of this site)
- Some mention the cultural relevancy or community influence for today (which gets into practical, application aspects, which this site also avoids)
It is no wonder this site has had various discussions, power struggles, communication breakdowns, etc., when even a number of men who generally have a similar "theological" view vary so much in their own definitions.
There was a previous meta post regarding defining terminology that offered a good path to take. There it suggested doing a term at a time. Here the attempt is to group a number of terms together for definition, so that all the types of "theology" we might want to mention are defined in one place.
The ultimate goal is to have a single community wiki type answer that has been discussed, edited, and refined for what we as a community mean by different terms when we mention various "theologies" in our posts and comments.
Of course, as the other post noted (#4), I do believe any question or answer can locally define how they are using a term. This listing here is for those that do not wish to constantly define, but stick to a community consensus, and also provide a link source for educating others about the site and its terminology.