Vespers, whose name literally means shadows, is the traditional evening prayer of the Catholic Church. Its celebration was and is to take place when evening comes and lamps are lit, though Saint Benedict implies it should be done before any lamps are needed. The origins of this Office pre-date monasticism itself and are linked to the evening sacrifice of the Jewish Temple in Jerusalem at sunset. Like the prayer in common at sunrise, a protracted evening prayer was likely part of the liturgical life of the earliest monastic communities.

The structure of the two main prayer times of Lauds and Vespers has always been similar: psalmody, a lesson, response, hymn, New Testament canticle of Zechariah (at Lauds) or of Mary (at Vespers), a litany of intercessions, the Our Father, the Kyrie Eleison, and the concluding prayer. The placement of the hymn at the beginning of each and every office was an innovation of modern times that alters the tradition of a subtle variety within the ancient structure of the Divine Office. At the Little Hours the hymn begins the Office, but in the offices of Lauds, Vespers and Compline, Saint Benedict describes the hymn as coming in the middle of the office, after the chanting of the psalms, lesson and short response. At Vigils, the hymn is quite near the beginning, after Psalms 3 and 94. These minor variations gave each office a distinctive flavor, subtle though it be. Some monasteries have maintained the position of the hymn according to the Rule of Saint Benedict. Christ in the Desert restored the hymn to this place about twenty-five years ago.