The Creed confesses “one, holy, catholic, and apostolic Church.” For the Orthodox, the Church is not first an organisation but a living reality: the Body of Christ, the communion of all who are united to Him and to one another in the Holy Spirit. She is one, because Christ is one; holy, because He is her holiness; catholic, because she is whole and lacking nothing; apostolic, because she holds the faith of the apostles unbroken.
This is why the Church cannot be reduced to a building or a bureaucracy. She is where the faithful are gathered around the bishop and the Eucharist, where the Gospel is preached and the Mysteries are celebrated, heaven and earth meeting at the altar. To be a Christian, in the Orthodox understanding, is not a private arrangement with God but a life within this Body.
The Church is also a hospital for the soul, in the Fathers' favourite image, not a museum of the perfect but a place of healing for the sick, which is to say, for everyone. She teaches, she absolves, she feeds; and everything she does is ordered toward one end: the union of the human person with God.