François Couperin's "Offertoire sur les grands jeux" from his "Messe pour les Paroisses" (Parish Mass) showcases the grandeur of the French classical period. Both his Masses feature an extensive offertoire which is the longest and most elaborate movement in each work. During the 17th and 18th centuries, French organ masses were designed to alternate with or replace sections of the sung Mass. These masses also included shorter movements for the Kyrie, Gloria, Sanctus, Benedictus, and Agnus Dei, each tailored to its liturgical function. A meditative Elevation piece for the consecration and a Communion movement were also present. The Mass concludes with a short Deo Gratias. This structure allowed organists to complement the entire liturgy with varied registrations and musical textures appropriate to each part of the service.
Score: https://www.sheetmusicplus.com/en/product/couperin-mass-for-the-parishes-19378648.html?aff_id=478282