MB recommends I read this piece by Archimandrite Grigorios Papathomas:
OUR 'POST‐ECCLESIOLOGICAL' AGE (pdf) [alternative link]
Related links:
Our 'Post-ecclesiological' Age Koinonia
pastoral mission by F. Papathomas
Solidarity and Justice in the Baltic Countries
Canon 28 of the 4th Ecumenical Council – Relevant or Irrelevant Today? (alt)