I suppose they’re irrevocable in the sense that we’re not going to stop believing and teaching what we have believed for the last 2,000 years, and we do also teach that we are the one holy catholic and apostolic church of God, but I have a feeling that you’re really wanting to know if we have anything like the Roman Catholic magisterium and/or something like Papal infallibility for our patriarchs. The answer to both of those questions would be no. There is no Orthodox magisterium (there are synods and councils, but they don’t really function like the RC magisterium does, since the magisterium works together with the infallible Roman Pope, and we don’t have anything like that), and no bishop in Orthodoxy is considered to be infallible.