Office for Notre Dame de la Mercy, approved on March 18, 1679
This text in the scanned pages below was set to music by Marc-Antoine Charpentier the very year it was approved by Rome: Antiphona in honorem beatae Virginis a redemptione captivorum (H. 25). He copied the work into cahier 22, which contains works written in 1679. Only a few year earlier, Mlle de Guise had been given a private chapel at the Church of the Fathers of Notre-Dame de la Mercy, situated just across the street from the entrance of her palace, the "Hôtel de Guise." This office was exclusive to the Mercy and was recited on its highest feast day, Saint Mary of the Snows, Festa S. Mariae ad Nives, on the Sunday closest to the Feast of the Assumption (August 15).
The text that Charpentier set for his Antiphona appears on the third page of this document, highlighted in grey and with marginalia in my hand to the left. I found this text in the Fonds théologique of the Médiathèque of Rodez, bound with a Brevarium Augustinianum, ad usum Fratrum, et monialium totuis Ordinis Eremitarum S. Augustini Juxta Brevarium Romanum [Pars Aestivalis], published by J.B. Coignard, Paris, 1684; library call number T. 1019. The somewhat greyer characters were printed in red ink.