How can you tell it's an Episcopal Church??? If they are using The Book of Common Prayer, it is! There is no other feature that so marks Anglican worship as does this remarkable book of services, prayers and scripture. The word "amnesia" means to forget. The Book of Common Prayer is an anamnesis: that is, a remembering. So long as it is used in services of private and public worship, the Christian message will be faithfully remembered and preserved. Through the years, it has been revised in order to be flexible to changing language and culture, but the core message it contains has remained consistently intact.
But whi is so lovely and meaningful a collection of prayers and scripture called "common"? The word common was once used to mean regular, or in cycles. "Common" also means that everybody does something together, or in common. The Book of Common Prayer is designed for the regular, week-to-week services and events of a worshipping community. It may be used for personal devotion, but its chief use is for all people when they are gathered together for worshipping.
When we close a service with "Let us bless the Lord" followed by the response "Thanks be to God", we are saying words that have been said by Christians since before the seventh century. When we hear the words of Eucharistic Prayer C "...the vast expanse of interstellar space, galaxies, suns, the planets in their courses", we know that only a contemporary person can say such a thing. The Book of Common Prayer continues to speak to us about the changeless; however, it does so in the changing local language adapted to our time and place.
The formation of The Book of Common Prayer is the story of our own history as a church. It is also the expression of a type of spirituality which is down-to-earth, inclusive of others, and deeply responsive to the Holy.