I agree with a lot of what has been said above, but I just want to make a few points below that I think will be helpful...
It's obviously the same situation with Hebrew. Learning modern Hebrew will only assist in learning biblical Hebrew, but learning modern Hebrew is not sufficient for proficiency in the biblical language. I think we'll agree that the case is the same with modern Greek and the biblical or classical form of the language.
Modern Hebrew is considerably more similar to Biblical Hebrew than Modern Greek is to Koine Greek. Morphology basically has 90%+ overlap (without having to convert things in your head first). Conventional pronunciations of Biblical Hebrew also follow the Modern pronunciation, so that is also not an issue.
After learning a couple of basic rules (like the infinitive has been subsumed under the subjunctive and αυ- drops from αυτός-ή-ό), it really mitigates the appearance of being different. I think the appearance is what throws many people off after a short amount of studying MG.
I agree with you here, but some of these differences are easier to adjust for linguistically minded people. I am assuming you are a "language person" to some degree. It would be interesting to note the experience of those who do not have a general aptitude for languages.
1. It has already helped my KG dramatically. I just spoke with a KG speaker today and I could understand 95% of what he was saying, that 5% is probably owing to pronunciation.
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3. I met too many natives, both young and old, educated and not, who could read and discuss much of what I put before them from the GNT.
4. One of my language teachers called Hebrews MG after I had her read a portion... <<Τι είναι το πρόβλημα, παιδί μου;; Αυτό είναι νέα ελληνικά!>>
Let me share some of my experience interacting with Modern Greeks about my materials (i.e., videos and lectures in Koine Greek with a restored Koine pronunciation). There are a number of Greeks who comment on what I have done and say things like, "I could understand basically everything!" "This is great!" etc. However, on one occasion, I had someone respond by saying, "Whatever this guy is doing, it isn't Greek! This is terrible!"
Now how could I get such drastically different responses from Modern Greek speakers?
This last person was a heritage speaker.
This person was living in America but had Greek heritage. Do you know what that tells me? If someone doesn't grow up with the typical Greek exposure to ancient language (whether through the standard education in school or through liturgy, etc.), their ability to approach Koine simply based on spoken Modern Greek is severely diminished. This person did not even recognize it as Greek! And yet native Greeks living in Hellas have told me that they understand almost all of what I produce in Koine.
I think this heritage speaker is a good comparison for what is being suggested.
While I think that Modern Greek is certainly helpful, expecting a non-linguistically minded person to only learn Modern Greek and then transfer to the New Testament is optimistic.
Ideally, one should learn both together.
Jonathan Haley wrote: ↑July 1st, 2019, 8:46 am
Personally, I’m likewise convinced that the need for any other pronunciation scheme than the one the Greeks themselves use is unnecessary.
I'm not sure that is the case. While Modern pronunciation is certainly better than Erasmian--and I think those who already have Modern Greek should keep that pronunciation when they read ancient texts--it does not replicate the phonemic contrasts present in the Koine period for one only learning Koine Greek.
Jonathan Haley wrote: ↑July 1st, 2019, 8:46 am
It would seem better to me to learn the handful of pronunciation changes that are relevant to older forms of Greek and keep them in mind when needed (context has a wonderful habit of clarifying doubts, and we always have the printed text before us anyway).
For those who already have Modern Greek, yes that is optimal.
Jonathan Haley wrote: ↑July 1st, 2019, 8:46 am
I’m more than a little disheartened to see so many people adopting a reconstructed pronunciation scheme when, essentially, only a century later it was already the current pronunciation.
This is not accurate from a historical phonological perspective. There was a high degree of regional variation. If we're just talking about the vowel system, it probably did not mirror the Modern system universally until the Late Byzantine period, when υ finally merged with ι universally. What is interesting about a Late Byzantine date (perhaps 7th-9th century) for this change? Our first appearance of εσεις and εμεις instead of υμεις and ημεις appear around the 10th century. To me, that suggests that relatively soon after the vowel system became identical with Modern, the language itself began to change to accommodate this. This topic needs to be researched more thoroughly (it will take many years), but one possible interpretation of the data is that a universal Modern Greek pronunciation could not tolerate some aspects of the Koine language, such as these pronouns. The change to the Modern pronunciation system (universally) led to a change in the language.
This is not even to mention the developments in the consonantal system--which are less significant--but by no means were identical with Modern universally in the Roman period (or even the Byzantine period for some regional dialects).