The Hymn 'Deus creator omnium' is one of the four so called daily hymns that the tradition attributes undisputedly to Ambrose. These daily hymns are: the morning hymns 'Aeterne rerum conditor', 'Splendor paternae gloriae', the hymn for the Tierce (9 a.m.) 'Iam surgit hora tertia', and the above mentioned hymn 'Deus creator omnium'. 'Deus creator omnium' is an evening hymn. The liturgical assembly addresses it to God, giving thanks for the passed day, and presenting intercessions for the coming night. The hymn focuses on the remembrance of the passed day, with its sunlight 1,2-3, and labours, including the associated pains, physical as well as mental 2,1-2; further there is a call to God: the chant of the hymn 4,1-2 expressing purity 4,3-4, prayer for repose 1,4; 2,1-3 and protection against the night's perils 5,1-7,4. [cf. Ps 141.] The final invocation of the Divine Trinity 8,1-4 joins prayer with theology. The structure of the hymn is akin to the Psalms: it is an evening prayer, as are the Ps 4 and 141, with an opening invocation of God by His name, and using forms of ancient prayer: praise of the Creator, thanksgiving for his goodness, prayer for protection against temptation and the terrors of the night. The current 'Liturgia horarum' took this hymn for its own, and five verses of this hymn are recited at the First Vespers on Sundays of the first and the third week.