... In one, holy, catholic and apostolic Church ...
These words are from the Nicene Creed, the Symbol of Faith. “Church” as a word means those called as a particular people to perform a particular task. The origin of this word is in Greek, where the meaning includes the sense of being called out. Our Saviour shows this to us: “If you were of the world, the world would love its own. Yet because you are not of the world, but I chose you out of the world, therefore the world hates you” (John 15:19). The Apostle Paul also addresses this: “I beseech you therefore, brethren, by the mercies of God, that you present your bodies a living sacrifice, holy, acceptable to God, which is your reasonable service. And do not be conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God” (Romans 12:1-2). The Christian Church is the assembly of God's chosen people called to keep His word, to do His will and His work in the world and in the heavenly Kingdom.
In the Scriptures the Church is called the Body of Christ (see Romans 12; 1 Corinthians 10; 12; Colossians 1) and the Bride of Christ (see Ephesians 5; Revelation 21). The Church is likened as well to God's living Temple (see Ephesians 2; 1 Peter 2) and is called “the pillar and ground of the truth” (1 Timothy 3:15).
One Church
The Church is one because God is one: because the Father, the Son and the Holy Spirit are one. There can only be one Church and not many. And this one Church, because its unity depends on God: Father, Son and Holy Spirit, may never be broken. Thus, according to Orthodox doctrine, the Church is indivisible. Human beings may be in or out of the Church, but they may not and cannot divide it.
According to Orthodox teaching, the unity of the Church is the free unity of human beings in the truth and love of God. Such unity is not brought about or established by any human authority or juridical power, but by God alone. To the extent that human beings are in the truth and love of God, they are members of His Church.
Orthodox Christians believe that in the historical Orthodox Church there exists the full possibility of participating totally in the Church of God and that only sins and false human choices (heresies) put anyone outside of this unity. In non-Orthodox Christian groups, the Orthodox claim that there are certain formal variations, different according to groups, which, if accepted and followed by its participants, will become obstacles to their perfect unity with God and will thus contribute to the destruction of the genuine unity of the Church (e.g., the papacy in the Roman Church).
Within the unity of the Church man is what he is created to be and can grow for eternity in divine life in communion with God the Father through the Son in the Holy Spirit. The unity of the Church is not broken by time or space and it is not limited merely to those alive upon the earth. The unity of the Church is the unity of the Blessed Trinity and of all of those who live with God: the holy angels, the righteous dead, and those who live upon the earth according to the commandments of Christ and the power of the Holy Spirit.
Holy Church
The Church is holy because God is holy: because the Father, the Son and the Holy Spirit are holy. The holiness of the Church comes from God. The members of the Church are holy to the extent that they live in communion with God.
Within the earthly Church, people participate in God's holiness. Sin and error separate them from this divine holiness as it does from the divine unity. Thus, the earthly members and institutions of the Church cannot be identified as holy in the same way that the Church herself is holy.
The faith and life of the Church on earth are expressed in its doctrines, sacraments, scriptures, services, and saints which maintain the Church's essential unity, and which can certainly be affirmed as “holy” because of God's presence and action in them.
Catholic Church
The Church is also catholic because of its relation to God: Father, Son, and Holy Spirit. The word catholic means full, complete, whole, with nothing lacking. God alone is full and total reality; in God alone is there nothing lacking.
Sometimes the catholicity of the Church is understood in terms of the Church's universality throughout time and space. While it is true that the Church is universal -- for all men at all times and in all places -- this universality is not the real meaning of the term "catholic" when it is used to define the Church. The term "catholic" as originally used to define the Church (as early as the first decades of the second century) was a definition of quality rather than quantity. Calling the Church catholic means to define how it is, namely, full and complete, all-embracing, and with nothing lacking.
Even before the Church was spread over the world, it was defined as catholic. The original Jerusalem Church of the apostles, or the early city-Churches of Antioch, Ephesus, Corinth, or Rome, were catholic. These Churches were catholic – as is each and every Orthodox Church today – because nothing essential was lacking for them to be the genuine Church of Christ. God Himself is fully revealed and present in each Church through Christ and the Holy Spirit, acting in the local community of believers with its apostolic doctrine, ministry (hierarchy), and sacraments, thus requiring nothing to be added to it in order for it to participate fully in the Kingdom of God. The wholeness of the Church in each place is focussed on each diocese (on each bishop with the rational sheep entrusted to him), and on the living relationship of communion in Christ between that diocese and all the other dioceses with their bishops.
To believe in the Church as catholic, therefore, is to express the conviction that the fulness of God is present in the Church and that nothing of the “abundant life” that Christ gives to the world in the Spirit is lacking to it (see John 10:10). It is to confess exactly that the Church is indeed “the fulness of Him who fills all in all” (Ephesians 1:22; see also Colossians 2:9).
Apostolic Church
The word “apostolic” describes that which has a mission, that which has “been sent” to accomplish a task.
Christ and the Holy Spirit are both “apostolic” because both have been sent by the Father to the world. It is not only repeated in the Scripture on numerous occasions how Christ has been sent by the Father, and the Spirit sent through Christ from the Father, but it also has been recorded explicitly that Christ is “the Apostle ... of our confession” (Hebrews 3:1).
As Christ was sent by the Father, so Christ Himself chose and sent His apostles. “As the Father has sent Me, I also send you ... Receive the Holy Spirit” (John 20:21-22), the risen Christ says to His disciples. Thus, the apostles went out to the world, becoming the first foundation of the Christian Church.
In this sense, then, the Church is called apostolic: first, as she is built upon Christ and the Holy Spirit sent by the Father and upon those apostles who were sent by Christ, filled with the Holy Spirit; and secondly, as the Church in her earthly members is herself sent by God to bear witness to His Kingdom, to keep His word and to do His will and His works in this world.
Orthodox Christians believe in the Church as they believe in the Father, the Son and the Holy Spirit. Faith in the Church is part of the credal statement of Christian believers. The Church is herself an object of faith as the divine reality of the Kingdom of God given to human beings by Christ and the Holy Spirit; the divine community founded by Christ against which “the gates of Hades shall not prevail” (Matthew 16:18).
The Church (and faith in the Church) is an essential element of Christian doctrine and life. Without the Church as a divine, mystical, sacramental, and spiritual reality, in the midst of the fallen and sinful world, there can be no full and perfect communion with God. The Church is God's gift to the world. She is the gift of salvation, of knowledge and enlightenment, of the forgiveness of sins, of the victory over darkness and death. She is the gift of communion with God the Father through the Son and the Holy Spirit. This gift is given totally, once and for all, with no reservations on God's part. She remains eternally, until the close of the ages: invincible and indestructible. Human beings may sin and fight against the Church; believers may fall away and be separated from the Church; but the Church itself, the "pillar and ground of the truth" (1 Timothy 3:15) remains eternally.