[quote="The_Scott, post:1, topic:302335"]
I have recently decided to go through the nitty-gritty, headache inducing details of the theology of the Holy Trinity. Now, I understand that there is a language barrier when translating the Greek into Latin theology, and visa versa.
For example, Latins say that the Trinity is "three personae in one substantia;" the Greeks would say "three hypostasis in one ousia." "Hypostasis" literally means "substance," (substantia) and thus Western theologians may see the East worshiping three gods. Likewise, if we translate the Latin "personae" (persons) into Greek equivalent, it would say "three masks in one substance," which is the heresy of Modalism.
However, my question is: why is there a difference in these terms? What is the difference between the Western "substantia" and the Greek "hypostasis"? Why couldn't the West have said "three substantia in one essentia"? I know that we adopted "substantia" instead of "essentia" because, I believe, the former was used more often than the latter.
I suppose if I had good, straight forward definitions of each term, I can understand it easier.
I believe that there was a time when ousia and hypostasis were terms that were largely interchangeable, and that it was the Cappadocian Fathers who purposefully gave the two terms the meanings we now associate with them as they articulated their understanding of trinitarian theology in opposition to the Arians and the Pneumatomachi. If this is correct (I'm not entirely sure, but I believe it is), then it may be part of the answer to your question. Also, I believe that for the Greeks to have later adopted the language of prospon, instead of hypostasis for "person" was made problematic both by the way that term was understood among the Greeks, as well as by the way it had been used heretically. Again, I'm not entirely sure-I'm several years removed from my studies.