Les Vèpres du Commun des Saints Op.51

Vincent d'Indy (1851 - 1931) became (at the advice of his friend Henry Duparc) a (devoted) student of César Franck at the Conservatoir du Paris. Inspired by his own studies with Franck and dissatisfied with the standard of teaching at the Conservatoire de Paris after Franck's death, d'Indy, together with Charles Bordes and Alexandre Guilmant, founded the Schola Cantorum de Paris in 1894. D'Indy taught there and later at the Paris Conservatoire until his death. Among his many students were Isaac Albéniz, Leo Arnaud, Joseph Canteloube (who later wrote d'Indy's biography), Pierre Capdevielle, Jean Daetwyler, Arthur Honegger, Eugène Lapierre, Albéric Magnard, Rodolphe Mathieu, Darius Milhaud, Cole Porter, Albert Roussel, Georges-Émile Tanguay, Otto Albert Tichý, Emiliana de Zubeldia, Xian Xinghai, Edgar Varèse and Erik Satie. The two last mentioned soon outgrew his lessons and made ​​him a laughing-stock. That has set the tone of many judgments about D'Indy (like that of Pierre Boulez), but in the 21st century there is some change and increasingly his importance is recognized. Few of d'Indy's works are performed regularly today, mainly his symphonic work. He was organist at the St. Leu-La-Foret church in Paris. He wrote only three pieces for Grand Orgue which I post to CCH today.
Les Vèpres du Commun des Saints Op. 51 (1899), dedicated to Alexandre Guilmant, are a series of 8 short pieces for the "Commun d'un Martyr (Hors du temps Pascal)". I don't know what the religious meaning of this is precisely. Maybe some of you that are more familiar can explain. These pieces have a clearly roman catholic liturgical background and are based on Gregorian melodies.