Density of light is an anthem that sets an evocative hymn by Thomas Troeger. The text is drawn from an Epiphany reading and explores the theme of the triumphing of light over darkness. The organ opens with a rising and falling quaver motif that is taken and expanded upon in the vocal lines. Expanding into dramatic homophonic textures, the piece ends with the words 'glory be to you O God' sung to powerful fortissimo chords.