Introit
A hymn, psalm, or anthem that is sung as the ministers enter to begin the eucharist. The term is from Latin, “to go in” or “enter.” The use of an introit psalm at the entrance of the clergy was introduced into the Roman liturgy by Pope Celestine I (d. 432). The choir sang the psalm text, and the congregation repeated an antiphon after each psalm verse or group of verses. The antiphon for the introit was typically a verse of scripture. The theme of the introit was suited to gathering the congregation for worship, or possibly the season, feast, or occasion of the day. The introit continued as long as needed to accompany the entrance procession. After reaching the altar, the presider would signal the choir to stop the introit. The entrance psalm would then conclude with the Gloria Patri, which resolved the introit and focused attention on the salutation and readings that followed. By the late middle ages, the introit was reduced to an antiphon, the first verse of the chosen psalm, and the Gloria Patri. Luther preferred use of whole psalms for the introit instead of just one verse. The 1549 BCP used short psalms and sections of Ps 119 for the introit. The 1552 BCP did not include entrance psalms, but permission was given during the rule of Queen Elizabeth for a metrical psalm or hymn to precede the liturgy. The 1979 BCP provides that a hymn, psalm, or anthem may be sung before the opening acclamation of the eucharist (pp. 323, 355).
Glossary definitions provided courtesy of Church Publishing Incorporated, New York, NY,(All Rights reserved) from “An Episcopal Dictionary of the Church, A User Friendly Reference for Episcopalians,” Don S. Armentrout and Robert Boak Slocum, editors.