Ecclesiology Gone Rotten

Francis, there was a great deal of obfuscation in your last answer. You seemed to be saying that a Christian "must" leave a church if the Gospel is at stake (you didn't tell us how you understand that term), but you still seemed to be saying it was more than acceptable to leave for lots of other doctrinal issues. Of course, the issue is not if "one elder" teaches it, the question pertains to Orthodoxy where the whole church teaches it.

To try and nail you down, let's take some specific churches. Let's take churches of the Three Hierarchs, Basil the Great's church of Caesarea, Gregory the Theologian's church of Nazianzus, and John Chrysostom's church of Antioch or Constantinople, as well as the West's favourite son, Augustine's church in Hippo.

Which of these church leaders taught the gospel? Which of them didn't teach the gospel? Is Eastern Orthodoxy's teachings different to what they taught as pertains to the Gospel? (document your answer if in the negative).

And finally, given you have given "the gospel" as the only certain criteria for leaving a church, is there any need to leave the Orthodox Church?