The mission of the church, within the framework of the Protestant Episcopal Church of America, is to implement Christ’s directive to his disciples: to love the Lord with all one’s heart and mind, and to love one’s neighbor as oneself. This mission is expressed in three broad ways, through Liturgy; through Fellowship; and Outreach.

Liturgy includes communal worship services with a primary emphasis on Eucharist-centered celebrations, but encompasses an educational program for children, adults and newcomers, as well as private Bible study and private prayer.

Fellowship includes relations with the Diocese, with regional organizations of the Episcopal church within the Diocese of Maine, with the community and among members of the church itself.

Outreach encompasses supporting relationships with persons, communities and
others in various kinds of need. It also includes mutually-supportive relationships with those who represent other branches of the Christian faith and other communities of believers.

These broad categories of the mission of St. John’s are carried out by establishing a network of measurable goals that reflect the administrative, financial and social structures of St. John’s Episcopal Church.

From the founding of St. John’s in 1835, music has been an important part of its services of worship and is an integral part of the life of the parish.

The music program at St. John's includes the Parish Choir, monthly Choral Evensong services, Annual Choir School, guest choirs & soloists, participation in community events, and organ recitals. The St. John's Parish Choir's latest recording of sacred music, Sing my Soul, is available on CD and cassette.