Etymonline.com

Historical

early 15c., “of or pertaining to history, conveying information from the past,” with -al (1) + Latin historicus “of history, historical,” from Greek historikos “historical; of or for inquiry,” from historia (see history). For sense differentiation, see historic. Meaning “narrated or mentioned in history” (as opposed to what is fiction or legend) is from 1843. Related: Historically.

Theology

mid-14c., “the science of religion, study of God and his relationship to humanity,” from Old French theologie “philosophical study of Christian doctrine; Scripture” (14c.), from Latin theologia, from Greek theologia “an account of the gods,” from theologos “one discoursing on the gods,” from theos “god” (from PIE root *dhes-, forming words for religious concepts) + -logos “treating of” (see -logy). Meaning “a particular system of theology” is from 1660s.

Discussion/Explanation

Historical theology is one of the 4 main branches of theology that is often closely tied with studies of church history. Why?

The answer to this question – because the focus of historical theology is to study the development of doctrine historically. Those that followed directly beyond the apostles largely spent their time reiterating what was already written by the apostles. Some of the biggest developments of this time were in the form (or liturgy) of early worship gatherings and an emphasis on the deity of Christ (even more so than what is described in the NT).

Much of historical theology focuses on such developments in their historical context. Our current understanding of God’s Word has come to us because of the many events that have occurred from then to now.  Chief among these events were challenges to the faith that often came in the form of heresies. Through such heresies, it became clearer the difference between the fact and fiction, the truth and falsehoods surrounding the faith.

Besides chronological developments and doctrines, we also see territorial developments and denominational developments as we study historical theology. This grants us understanding as to how such groups and divisions have come to be and inform us on how to view them today.

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