In order to hear a performance of the Alexander Nevsky Choir, which is known as the best orthodox choir in Bulgaria, I attended an orthodox service at the Alexander Nevsky Cathedral on Saturday - a very impressive place indeed! As was the service, of course, even though, if you think that the roman-catholic church is conservative, think again! Compared to the orthodox church, it's highly progressive.
For starters, I don't know much, if anything, about the orthodox liturgy, but observing the service as an outsider was very instructive. And of course it reminded me of that time when I was the best man for my friend F.'s orthodox wedding in a tiny historical church just outside Kiev (Ukraine). That was a memorable, albeit somewhat strenuous experience, since it included holding a rather heavy brass crown over the groom's head for the duration of the service at a temperature that felt like 50 degrees ...
The language used is a mediaeval slavonic bulgarian that hardly anyone understands anymore nowadays. Then, the priests (or popes, I think - all 8 of them) usually turn their backs towards their congregation (which incidentally was quite small, and standing (there's no seats), and interestingly enough including the outgoing Bulgarian Prime Minister & former king, Simeon II Sakskoburgotski with two bodyguards - there's a government crisis going on just now, don't you know). Also, I don't think there is an actual sermon given - the service seems to consist of a rather byzantine (literally!) sequence of scripture readings, benedictions, sung interaction between popes & choir, and several incense equipped walkabouts. Instead of the communion, people line up to kiss an icon, which is evidently something done very regularly. Another thing that is to be kissed is a visiting pope's hand. It might even have been Patriarch Maxim, judging by his looks, age & the reverence paid to him - what's more, his residence is just across the street, so he probably just drops in occasionally.
As for the music, that was altogether otherworldly. Naturally, it is only vocal since there are no instruments in an orthodox service. And there is no polyphony either (that was considered sinfully profane), but the singing is extremely polychromatic and goes straight to your heart. Indescribable, so I won't try it.