Last spring I was introduced to some current work in conceptual history (Begriffsgeschichte) through a seminar at the Committee on Social Thought, and it has since been an interest of mine that I look forward to reading more about when I have the time. I think that there could be some significant interaction between theology and the history of concepts, and my recent readings in American pragmatism have also brought up thought-provoking tensions over the very idea of a concept... tensions that might be fruitful for work on their history.
Conceptual history is of German origin, with some important philosophical lexicons and encyclopedias paving the way for the 20th century resurgence of the project in publications such as the Archiv für Begriffsgeschichte. The international reception of conceptual history has also grown in recent years, and from what I can tell has primarily concerned itself with the history of concepts in political thought. This is the primary focus of the two main publications outside of Germany, the Finnish Redescriptions and the newer journal Contributions to the History of Concepts, which was established following a meeting of the History of Political and Social Concepts Group in Rio de Janeiro. My initial introduction to concept history was through this more recent reception in the history of political thought.
Despite the strong focus on politics, it strikes me as pretty obvious that theology and religion more generally offers a number of places for interaction with this field. Isidore's Etymologies is only the most prominent example of a long interest in a theoretical examination of concepts in Christian thought, extending to the work of Kittel et al. that is such a part of the 20th century biblical studies landscape.
On the other hand, 20th century American pragmatist thought could provide a helpful reconsideration of the very idea of the concept, and suggest some new theoretical avenues for historical work. I'm not aware of the current state of interaction-- there may in fact be some conceptual historians working from a pragmatist perspective. But Davidson's criticism of incommensurability of conceptual schemes or Brandom's concern for the development and use of concepts as they apply to normativity and self-consciousness could probably do a lot of work if read alongside a project of concept history.