Genealogists spend a lot of time researching in old church records. In many cases, if it were not for records found within the world’s chuches, genealogists would have no records to turn to at all. Understanding the various religions is impotant to understanding our ancestor’s lives, as their lives were very much tied to their religion.
There’s an interesting website found online called opposingviews.com. It deals with controversial stuff, much of it taken from the day’s news. One of the subjects they deal with a lot is religion. I happened to run across an article entitled “Similarities Between Byzantine Orthodox & Catholicism” that you might find interesting. If you take a look at the side-column, you will note that there are numberous article comparing religions.