"One of the things that is distinct about the Orthodox Church as compared with both Catholics and Protestants is that we have no actual mechanism in place — neither an infallible and supreme papacy nor any kind of democracy — for making alterations to the substance of the Christian faith. No one may decree, nor may any body vote, to change the dogma and core praxis of the Church.
That is one of the reasons why I can't get excited about theories that the Church will be destroyed by people who say wrong things.
The reality is that, every Sunday, there are 1000+ heresies spoken at coffee hour and even some in sermons (not to mention the probably millions of heretical comments that appear every day on the Internet), yet the Church doesn't get altered by this impurity of opinions. That's because the Church isn't a purity cult -- unlike some religious sects.
If someone actually manages to lead a lot of people astray such that parallel hierarchies are set up, then there are conciliar remedies to deal with this. In many cases, God Himself cuts off leaves and branches that are withering and harming the rest of the vine.
That last point is the most important, by the way -- while each of us is called to keep ourselves as pure and clean in faith as we can, and while some are given the pastoral responsibility of purifying those God has placed in their care, it is ultimately God Who prunes and chastens those who need it.
The franticness and anxiety come when people forget that God has not abandoned His Church, and they treat it as though it's merely a human institution that can be successfully altered by humans.
It can't. The question for each of us is not whether the Church will fall away but whether we ourselves will. So, the main thing is for each of us to look primarily to his own soul and to the souls God has given us". By Fr. Andrew Stephen Damick