The original Nicene Creed, composed at the first two Ecumenical Councils in the fourth century and used in the Church to this day, expresses the essential teaching of the Orthodox Church. The heart of this teaching is that the eternal Son of the eternal Father became man in the person of Jesus Christ while remaining fully God in order to reveal God to man and unite man To God. He did this through His birth, life, death on the Cross, Resurrection, and Ascension into Heaven.
Orthodox Christians follow the ancient forms of Christian worship, which are rooted in the Jewish Synagogue and Temple, and their services are full of Scripture. The services are entirely sung or chanted, never read in a conversational tone. The worship is wholistic, addressing and involving the whole person including the mind, the body, and all the senses: sight, hearing, smell, taste, touch.
Icons adorning the iconostasis and the walls of the church affirm the reality of Christ's Incarnation--that the eternal Son of God became fully man while remaining fully God. As man, He was visible and revealed the invisible Father to man. (As He said to Philip, "If you've seen Me, you've seen the Father.") The icons of Mary, His mother, the Theotokos ("God-bearer") always include her Son to proclaim the reality of the Incarnation and man's need to participate in his salvation by feely saying "yes" to God as Mary did. The icons of the saints reveal how sinful humans become holy and become conformed to the image of Christ and partakers of the divine nature (2 Peter 1:4). Christ shows through His saints what each Christian is to become--holy bearers of Christ in a fallen world.
Incense is part of man's offering to God as it was in the Old Testament. It indicates the presence of the Holy Spirit in the Church and reminds worshippers that God receives their true prayer as a sweet fragrance (Revelation 8:3-4).
Orthodox Christians worship standing for three reasons: out of respect for Christ the King, as a sign of the Resurrection (Christ has raised us up with Himself), and because worship is properly an active work of the people, not passive listening or entertainment.
Candles used in Orthodox worship represent the light of Christ that each Christian is to shine in the world and the warmth of zeal for the Faith and of love for God and man that must burn in the heart of each believer, who is called to walk in the Light of Christ rather than darkness and to be hot towards God rather than cold or lukewarm. The candle also represents an offering to God, showing that in true worship we offer ourselves to Him as living sacrifices. Orthodox prayer is always offered with burning open flame.
Orthodox Christians often make the sign of the Cross, especially when the Holy Trinity is mentioned. The index and middle fingers of the right hand are pressed against the thumb, and the two little fingers are pressed against the palm. With the hand held in this fashion, the worshipper touches head, stomach, right shoulder, and left shoulder, and then bows. Making the sign of the Cross in this way confesses the Orthodox Christian's faith in the Holy Trinity (3 fingers) and Christ's incarnation in two natures (2 fingers) as perfect God and perfect man.
Orthodox priests are usually married in accordance with ancient practice.
The Eucharist (Holy Communion) is reserved for Orthodox Christians who have properly prepared themselves through prayer, fasting, and a recent confession with a priest. Apart from Communion, visitors and unprepared Orthodox are welcome to participate fully in Orthodox worship.