.....Given the apostasy of the papal church (the only church at the time), it would be easy to say that Christ has abandoned his church....
WRONG!!!! There was, and is, also the Holy Orthodox Catholic Church of the East. Despite its domination by islam at the time (even in Russia, which was struggling to overcome the Tatar and Ottoman yoke), Christ had not abandoned her, and she was and is the visible Church.
Luther well knew this. And many of our Missouri Synod Lutheran brethern, who know the Book of Concord better than we lied-to and spoiled ELCA folks do, know just how close we Lutherans really are to Orthodoxy, as well as the differences.
There will be a symposium in Detroit in September (10th-11th) to promote learning about Orthodoxy for Lutherans:
http://www.orthodoxdetroit.com/
After it is over, the talks will be avaiable on that website in audio form.
HS, could you ping us after the talks? I will try to keep up with them, but knowing my self I will probably forget.