Later the diurnal group of Terce, Sext and None was instituted for the sanctification of the middle of the day. (Matins might be called the parent-Office, and Vespers and Lauds the twins since they are identical in structure.) This group, nocturnal in origin, constitute the Greater Hours, and the other five, which are named below, the Lesser Hours. 'It is supposed that the watch of prayer which preceded the post-apostolic Eucharist was eventually organized into four parts, one of which remained as the preparatory part of the Eucharist (the Proanaphora or Mass of the Catechumens) but the other three became respectively, Vespers for the later afternoon, Matins for midnight, and Lauds for the early morning. The Anglican Breviary's General Rubrics provide insight into the origination of the Christian Divine Office: Then we all rise together and pray, and, as we before said, when our prayer is ended, bread and wine and water are brought, and the president in like manner offers prayers and thanksgivings, according to his ability, and the people assent, saying Amen and there is a distribution to each, and a participation of that over which thanks have been given, and to those who are absent a portion is sent by the deacons. On the day called Sunday, all who live in cities or in the country gather together to one place, and the memoirs of the apostles or the writings of the prophets are read, as long as time permits then, when the reader has ceased, the president verbally instructs, and exhorts to the imitation of these good things. Justin Martyr records a celebration of the Eucharist with the same Liturgy of the Word, followed by Liturgy of the Gifts, which Christians observe today: This service of preparation consisted largely of readings and psalms, and may have extended as far back as Saturday evening in accordance with the great respect paid to the Lord's Day and the Jewish custom of reckoning days from sunset to sunset. In addition, the early Sunday Eucharist had an extended 'watch' or 'vigil' prior to its actual celebration.

In accordance with Psalm 119:164 - 'Seven times a day do I praise Thee' - devout Jews would offer prayers and psalms periodically throughout the day, and such services were a feature of synagogue worship in the days of the Apostles. Regular daily prayer appears to have both been inherited from the Jewish Church and an outgrowth of the extended apostolic Eucharist.

From the earliest days of the Church, there have existed two main forms of liturgical Christian worship: the Holy Eucharist, and the daily round of prayer known as the the Divine Office, the Liturgy of the Hours, or the Daily Office.

Divine office lauds