katherineofdixie: I'm more familiar with Christian history than most, but certainly not as well informed as some. I have attended an OCA liturgy.
I ask because liturgical worship has been the way that the Church, the Body of Christ, has always worshipped God. If you read St. Justin Martyr or the Apostolic Constitutions you will find liturgical worship.
Indeed Lutherans, Roman Catholics, Episcopalians (to name a few) have all more or less continued in that tradition of liturgical worship, so that visitors from those faith communities find the Liturgy both accessible and familiar. It seems to be mostly (forgive me) visitors from other newer faith communities (who sometimes act as if they count it a virtue to excise all vestiges of historical Christianity from their theology, worship and praxis) who find Orthodox worship to be difficult or strange.
"The worship of the Orthodox Church is viewed as the Church's fundamental activity because the worship of God is the joining of man to God in prayer and that is the essential function of Christ's Church. The Orthodox view their Church as being the living embodiment of Christ, through the grace of His Holy Spirit, in the people, clergy, monks and all other members of the Church. Thus the Church is viewed as the Body of Christ on earth which is perpetually unified with the Body of Christ in heaven through a common act of worship to God.
...the Orthodox draw no distinction between the Body of Christ in heaven and those on earth viewing both parts of the Church as inseparable and in continuous worship together of God. Orthodox worship therefore expresses this unity of earth and heaven in every possible way so that the earthly worshippers are continually reminded through all their senses of the heavenly state of the Church. The particular methods for doing this are very far from arbitrary but have been passed down from the earliest periods in Christian history through what the Orthodox call "Holy Tradition"."http://en.wikipedia.org/wiki/Eastern_Orthodox_worship
“The earliest and clearest reference to liturgy comes in Acts, the book which chronicles the inception and growth of the early Church. The church at Antioch was the first Gentile church outside of Jerusalem, established approximately A.D. 38 when Barnabas was sent to teach there (Acts 11:25 ff.). Acts 13 describes the selection of Barnabas and St. Paul for the first missionary journey. This would have taken place approximately A.D. 46, in what by then was a well-established and structured community of believers.
Luke records that the calling of Paul and Barnabas was the work of the Holy Spirit, and that it took place during the “liturgy”. The text reads, “as they were ‘liturgizing’ (leitourgounton) before the Lord and fasting, the Holy Spirit said ‘Set apart for me Barnabas and Saul to the work to which I have called them’”(Acts 13:2).”http://www.stgabrielashland.org/historical-origin-of-orthodox-worship/