Gloria In Excelsis Deo is Latin for Glory to God in the Highest. This Gloria is from the Missa de Angelis, a fifteenth or sixteenth century plainchant Mass setting which is still sung regularly in many Churches throughout the world. Plainchant, the official music of the Church, is sometimes termed Gregorian Chant as it is said to have its origins in the era of Pope Gregory (590-604) although it was not written down until the ninth or tenth centuries. During Mass, the cantor or precentor sings the parts marked 'A' alternating with the Choir and congregation singing parts 'B' as can be heard on the recording. The Missa de Angelis is sung regularly during Solemn Masses in the Church of Saint Peter in Chains.

This recording of Gloria In Excelsis Deo by the choir was made on 24 July 2006.

The soloist was Father Stephen Motroni and the other choir members were Evelyne Agostini, William Brannan, Graeme Cunningham, Jim Donnelly, Alison Erskine, Joanne Holton, Stephanie Hume, Fiona Johnston, Kirsty Johnston, Catherine Kerr, Father Stephen Motroni, Jane Anne Muir, Robin Reid, Susan Small, Gordon Stevenson and Mary Catherine Swan.