The Orthodox Christian belongs to the Body of Christ, the Church of Christ. This Eastern Orthodox Church is organically the same congregation (or ecclesia) which was born at the outpouring of the Holy Spirit in Jerusalem on Pentecost, a direct continuation from the Apostles by laying on of hands from each generation of priests to the next. The Orthodox Christian recognizes the rich Christian heritage and proclaims that he belongs to this Church, which corresponds to the Church of the Apostles as does a grown-up person correspond to a picture taken of him as a child. The Orthodox Christian has been baptized in the name of the Holy Trinity and follows the ideals and beliefs of both the Scriptures and Sacred Tradition. He believes in a living and loving God, Whose Grace protects and guides him in the path of redemption. He believes that God has revealed Himself in the Bible through the Prophets and especially in the Person of Jesus Christ, His only-begotten Son who is man's Savior. He especially believes in the Incarnation of Christ as God-Man, in His Crucifixion and Resurrection, in His Gospel and Commandments, and in the world to come.
(Excerpts from THE FAITH WE HOLD by Archbishop Paul of Finland)
Who is God?
There is one God (Deut. 6:4). He is the creator of the everything that exists (Gen. 1:1), Who did this by Himself (Is. 44:24). God has always existed (Is. 43:10). God exists in three Persons: Father, Son, and Holy Spirit (28:19, Lk. 4:21-22). They are three, yet all distinct, (Jn. 14:26-28).
Who was Christ?
A better question would be "Who is Christ?" Orthodoxy confesses that Jesus is the Christ sent by God to redeem the world (Jn. 1:29). He is both God and man without mixing the two natures (Jn. 1:1, 20:28; 1 Tim. 2.5). He was born of the Virgin Mary, lived in the land of Judea, died, and rose from the grave. He then ascended into Heaven and will come again in the future.
Who was Mary?
Mary was the mother of the Lord Jesus, and since Jesus was God, she was also the Mother of God. In Greek, this is Theotokos. We call her Mother of God to affirm our belief that Jesus is God. Christ took His humanity, His very flesh, from her. In order to do this, she had to be very holy. Scripture also testifies to this, saying that she was "full of grace" Lk. 1:28. The Lord followed all the commandments of God and respected His Mother in the highest possible way, and at His death entrusted her to the Apostle John, because she had no one to care for her (Jn. 19:26). We, in turn, follow the example of the Savior and hold her in the highest regard for her holy life.
What is the Bible?
The Bible is an inspired collection of books that includes the Old Testament and the books of the New Testament. The Church collected these and determined its contents over the few hundred years. It is a collection of writings by men who were moved by the Holy Spirit to record God's revelations and is both divine and human (2 Pet. 1:20-21). As such, it is a powerful force for our salvation (2 Tim. 3:14-17).
What do Orthodox Christians believe about Salvation?
Salvation is the process of becoming Godlike. 2 Peter 1:4 says that we may "become partakers of the divine nature." Christ Himself prayed that we would be one even as He and the Father are one (Jn. 17:21). We do this by our faith in God (Eph. 2:8-9), godly works (Js. 2:21-24), and by participating in the Sacraments of God such as baptism and the Lord's Supper (Jn. 3:5, 6:53). However, whether it is faith, works, or sacraments, it is not we who save ourselves, but Christ Jesus who saves us (Gal. 2:19-20). Through this, we expect the resurrection of the dead (1 Cor. 15:51-52).
What is the Church?
We translate the Greek word ekklesia as Church, but it most literally means "assembly." Solomon was King of the Assembly of Israel, and we call one of his books Ecclesiastes in reference to this. God's Church, His Assembly, is His Body (1 Cor. 12:12-13). This is so much so, that when Christ rebuked Saul on the way to Damascus "Saul, Saul, why persecuteth thou Me?" (Acts 9:4) when he was persecuting the faithful. Christ established the Church at Pentecost when He sent down the Holy Spirit (Acts 2:1ff). Christ promised that the power of Hades, the power of death, would never overcome it (Mt. 16:18). Christ promised us that the Holy Spirit would guide His Church into all truth (Jn. 16:13). Because of these things, the Apostle Paul promised that the Church is the very foundation of Truth (1 Tim. 3:15). Because of this guidance, the Church is our ground and guide in faith. It is our assurance of the Scripture (2 Tim. 3.14-17) and in all other matters of faith.
Who are the saints?
The saints are people who, in this life, reached a pinnacle of godliness, and their examples are a shining star for us, and an assurance of the resurrection. The Apostle Paul says that neither life nor death can separate us from Christ (Rom. 8:38-39). Christ defended the resurrection by explaining that God "is not the God of the dead but of the living" (Mk. 12:27), and this is still more true now in light of the resurrection. With these people, we have an illustrious series of examples, a veritable cloud of witnesses (Heb. 12:1). The lives of these saints, and their many deeds, confirm the Gospel for us just as the lives of those Old Testament saints did.