Much of the organ’s historic repertoire (which dates to the 1400s) was written for use in Christian liturgical worship. Organ Vespers is a prayer service in the evening that gives music written for the organ an opportunity to speak fully within a liturgical context.

Organ Vespers at St. Peter’s follows An Order of Worship for the Evening in the 1979 Book of Common Prayer (page 109), essentially an ancient order of Evening Prayer, or what we also call Evensong.

Before the service, the church is in relative darkness and silence—there is no music before this service begins.

After the entrance of Officiant and the Vesper candle, the service begins with a thanksgiving for light called the Lucernarium. This ancient rite was the predecessor to the kindling of the new fire and lighting of the Paschal Candle at the Great Vigil of Easter. The traditional responsory sung during the candle lighting is also called the lucernarium.

The ancient Greek Phos hilaron (literally “hilarious light”) is among the oldest Christian hymns in use today. It was a regular part of the Lucernarium lamp-lighting ritual. The setting used for these Organ Vespers services was composed by Ronald Arnatt (1930–2018), who served as the Organist and Choirmaster for the cathedral in this diocese for twenty-five years.

This service then proceeds with late 19^th century and 20^th century organ music written in the Christian liturgical tradition.

The ancient Latin hymn “Vexilla Regis prodeunt” is preceded by an organ prelude by English composer Edward Cuthbert Bairstow (1874–1946).

The cantor and the organ together then sing the Canticle in alternation, a setting of the Magnificat by French composer Alexandre Guilmant (1837–1911). This organ work compliments based the traditional Mode 1 plainsong for this ancient hymn.

Two movements from a Partita on Crucifer by American composer Charles Callahan (1951–2023) are heard at the end of the service: 1) gentle Meditation before the singing of the hymn “Lift high the cross,” and 2) a rousing Chorale-Fanfare as the voluntary.

St. Peter’s organ was built by the Mander organ company of London, England, in 2001. The instrument has 56 ranks (2,979 individual pipes), playable on three manuals (keyboards) and pedal. Organ Vespers services were first held at St. Peter’s in 2021 to mark the 20^th anniversary of the organ.