As soon as he arrived, he had this small communal church in the department of Morbihan restored, decorating it with paintings that mixed the wonders of Celtic legend with the Christian faith, through the symbolism of the Holy Grail.

Because of his original and unconventional ideas, the diocese of Vannes probably wished to sideline him in this isolated rural village, accessible only by dirt roads, whose church was falling into ruins.

[9] The artworks he commissioned include two wooden statues of Saints Onenne and Judicaël by the sculptor Edmond Delphaut, a series of stained-glass windows by Henry Uzureau illustrating the life of St Onenne,[10] a series of paintings, altarpieces and other fittings by Karl Rezabeck and Peter Wisdorff (both released German prisoners-of-war),[11] and a mosaic of the white hart of Brocéliande, symbolizing Christ, by Jean Delpech.

The Grail appears in the east window with Joseph of Arimathea and Christ, and it manifests itself to King Arthur and his knights in a painting above the sacristy door.

[12] Morgan le Fay figures in one of a series of paintings on the Stations of the Cross, notable for setting the story in local Breton scenes.

[11] Gillard was putting himself in tune with the new socio-economic practices of his time, responding to the demands of tourism which had resulted from the arrival of paid holidays and the progress of the automobile.

[9] The first tours were created in the post-war years: coaches went on Sundays from Rennes to Tréhorenteuc, where Father Gillard was responsible for showing people around the Val sans retour.

[4] His last years were spent in a retirement home for clergy in Sainte-Anne-d'Auray, but he was still able to visit Tréhorenteuc thanks to the hospitality of Father Rouxel of the nearby village of Néant-sur-Yvel, and to meet admirers and enthusiasts.

[21] During his years of service as a priest, Father Gillard met Jacques Bertrand, alias Jean Markale, who has since been considered his spiritual heir.