His motto "Em Pob Emser Quelen" and the older Breton expression for "Better death than dishonour" figure in stained glass in the Lazarist church in the rue de Sèvres.

[1] Ordained in 1807, he served a year as Vicar-General of Saint-Brieuc and then became secretary to Joseph Fesch, uncle to Napoleon Bonaparte.

When the latter was exiled from his diocese of Lyon under the Bourbon Restoration, de Quélen exercised his ministry at Saint-Sulpice and in the military hospitals.

Under the Bourbons, he became successively spiritual director of the schools in the archdiocese, Vicar-General of Paris, and coadjutor archbishop to the Cardinal de Talleyrand-Périgord, succeeding the latter in 1821.

[2] Apart from official functions such as the christening of the Comte de Paris, the funeral of the Duke of Orléans and the Te Deum sung in honour of the French victory in Africa, he confined himself to visiting the parishes of the diocese, looking after the religious instruction of military recruits, and organizing his clergy.

[1] However, when the epidemic of 1832 broke out, he transformed his seminaries into hospitals, personally ministered to the sick at the Hôtel-Dieu, and founded at his own expense the "Oeuvre des orphelins du choléra".