Each of the day hours begins with the verse, "O God, come to my assistance; O God, make haste to help me(Ps 70:2)," followed by the Doxology and the appropriate hymn.

Then, on Sunday at Prime, four sections of Psalm 119 are said. At the other hours, that is at Terce, Sext and None, three sections of this psalm are said. On Monday three psalms are said at Prime: Psalms 1, 2 and 6. At Prime each day thereafter until Sunday, three psalms are said in consecutive order as far as Psalm 20. Psalms 9 and 18 are each divided into two sections. In this way, Sunday Vigils can always begin with Psalm 21.

The psalms for Prime and the day hours of the psalmody—Terce, Sext and None—are relatively ordinary. They simply recite Psalms 1–20 in order. But they do it with two major emphases. The first is the opening of the Office with the verse, “O God, come to my assistance,” the continuing reminder that even prayer is a gift from God.

The second is to form a kind of drumbeat for the highlight of the next week, the Vigil of Sunday that opens always with Psalm 21, which stands as both warning and promise. It details the underlying truth of life: the monastic is to remember, however powerless they may feel, that no ruler is as powerful as God; no ruler deserves our praise as does God; no ruler really rules anyone. However powerful particular rulers may seem, we know that in the end it is God who will prevail, it is God in whom we must put our trust.