If you want to study this in depth then you might read about the correspondence between the early Lutherans and Patriarch Jeremiah II regarding the Augsburg Confession, which you can read about in this book. You can also read about the EO Synod of Jerusalem in 1672 which rejected the Protestant teaching.
It really boils down to the solas. EO never held to sola scriptura and considers it a source of error. Protestantism doesn't exist without some form of it.
I've heard that this book is a good overview of early Protestant-Orthodox conversations.
Luther was just appealing to the idea of a Greek Orthodox Church to show that there were non-Roman Churches out there to give himself legitimacy. He hadn't actually considered their doctrines. He was just so convinced that he was right that he assumed non-Roman Churches would agree with him. When later Protestant scholars actually corresponded with the Orthodox on theology it did not go so well because they discovered that they were actually in agreement with nobody but themselves.
The Philokalia isn't so much a late work as a recently (lol) compiled collection of works on prayer. It's quite a lot and not something I'd put forward as an introduction even for a high-level reader. It's full of practical advice, but should still be taken under the guidance of one who is very experienced in a disciplined life of prayer, as more than a few, unfortunately, have seen some rigorous guidance meant for monastics, applied it without adjustment to their own lay life, and burned themselves out.
If you bear the above in mind and weigh the suggestions carefully, it can be a productive read.
Since your background in philosophy is so extensive and since you're so familiar with German thinking, <em>Augsburg and Constantinople: The Correspondence between the Tubingen Theologians and Patriarch Jeremiah II of Constantinople on the Augsburg Confession</em> offers translations of the debate over letters between Lutheran theologians and an Ecumenical Patriarch. They spend a lot of time discussing the place and role of Holy Tradition, and other Protestant-specific objections, but the whole conversation is generally informed by two fundamentally different approaches the Faith. The Lutherans ardently defend some Roman Catholic positions the Orthodox find objectionable, which was interesting to see.
But it does nosedive into some hard and very technical philosophical debate more rapidly than I anticipated, you may find it a less distressing experience than I lol
This is more for history buffs, so is not precisely what you are asking for. But if any are curious how us two first met to discuss similarities and differences, this is it.
This might interest you.
https://www.amazon.com/Augsburg-Constantinople-Correspondence-Theologians-Confession/dp/0916586820
It is some letters early Lutherans wrote to the Orthodox Patriarch in Constantinople. He wrote back what he liked and disagreed with, which started a dialogue. Spoiler alert: eventually the Patriarch said “I see you as friends, but don’t approach me on this again”.
I personally have two gripes. They do allow asking for “intercession” from dead saints. As they view it, it is no different than asking members of your church to pray for you. However isn’t asking for anything still praying?
Second is Theosis (deification). At best, this is just a poor choice of words and it just means returning us to our Adam like state prior to the original sin. At worst, it approaches what Mormons believe, and I know a few Mormons who like to use Theosis to justify “As God is we shall be”. I think the Orthodox view lies somewhere between the two extremes.
This book is a set of letters between 1570's Lutherns and Patriarch Jeremiah II. He really details the Orthodox view of the sacraments and other topics from scripture, tradition, and reason.
https://www.amazon.com/Augsburg-Constantinople-Correspondence-Theologians-Confession/dp/0916586820
There's a fascinating book called Augsburg and Constantinople, that's a collection of letters sent between some early prominent Lutheran theologians and the patriarch of Constantinople himself. I mean the exchange is just...well, fascinating. It's a bit of a dense read, but I highly recommend it.
Here it is in book form. Not sure if it is online somewhere as well.
If you're interested in reading the dialogue between the the theologians at Tubignen and Patriarch Jeremias II of Constantinople, you can find a translation of the letters on Amazon. Oddly and unfortunately, it doesn't contain a copy of the Augsburg Confession which was sent to Constantinople. Some excerpts can be found here, but be aware that this website tends towards the traditionalist end of the spectrum.
You're thinking of correspondence that happened between Lutheran theologians and Constantinople after Luther's death:
https://www.amazon.com/Augsburg-Constantinople-Correspondence-Theologians-Confession/dp/0916586820
The Orthodox attitude in practice is extremely varied. The ancient canons are one thing, but as you can see from the story in the OP of this very thread, they are not always followed. The current Patriarch of Constantinople has a very cordial relationship with the Catholic Church and has prayed together with every Pope for the last 30 years. On the other hand, when the Patriarch of Georgia met with Pope Francis in 2016, there were no prayers - only talking - and the Georgian Patriarchate asked the Orthodox faithful not to attend the public Mass celebrated by the Pope.
So there is a lot of intra-Orthodox disagreement on whether we should continue to maintain a healthy distance or adopt a more ecumenistic stance towards the rest of Christendom.
As such, it's hard to say how most Orthodox feel about the attention we receive from Protestants and Catholics. We strongly encourage everyone to become Orthodox of course, but they have to know what Orthodoxy is. Evangelicals who view Rome as non-Christian but hold a sympathetic view of Orthodoxy are going to be horrified when they find out that we also pray to the saints, we venerate the Virgin Mary, we cover our churches in images to a degree that makes Catholic churches look almost Dutch Reformed, and we don't even have precisely the same Bible that evangelical Protestants use. So we generally try to explain these things gradually so as not to scandalize evangelical inquirers.
With Lutherans, we've had an interesting relationship ever since the letters between the theologians of Tubingen and Patriarch Jeremiah II in 1575-1581. The general feeling is that Lutherans are the closest to us among all Protestants, and that they could become Orthodox relatively easily if they just let go of some of the theological baggage they've inherited from Catholicism.
Perhaps that is the reason why the road from Wittenberg to Constantinople is fairly regularly traversed!
With Catholics... opinions are VERY divided. They range between "our differences are really minor" and "the Pope is the father of all heresies for the past thousand years". But I think it's fair to say that most Orthodox, even the more pro-Catholic ones, are very annoyed at how modern Catholics like to pretend that we're just Catholics without a Pope. No we're not. Stop it.