René Descadeillas took it for granted that the “Dalle des Chevaliers” was an ancient relic, and was discovered by Abbé Saunière in his church in 1886; the dating of the sculpture is estimated to be approximately 12th-13th century. The interpretation of what the sculpture depicts is debatable.

The Dalle des Chevaliers cannot be accurately dated because stone cannot be Carbon-dated. There is no proof the relic was “discovered” by Abbé Saunière in 1886 just like there is no proof that the “Carolingian” pillar was used in Abbé Saunière's Church to support the Main Altar (originally termed the “Visigothic” pillar). We rely solely on the hearsay evidence of Abbé Saunière for the testimony of the “Carolingian” pillar. The earliest account of the “Dalle des Chevaliers” would seem to be in the article by Elie Tisseyre, during a trip to Rennes-le-Château in 1905, who described it as a tombstone: “But in a small garden adjoining the church one of us recognised a crudely sculpted (or rather engraved) tombstone as dating from the 5th century; it was unfortunate that this tombstone was being used as a step of a staircase and was therefore exposed to all the inclemencies of the open air.” (‘Excursion du 25 Juin 1905 à Rennes-le-Château’, Bulletin de la Société des Études Scientifiques de l’Aude, Tome XVII, 1906.)

Antoine Fagès described the Dalle des Chevalier thus: “In this carving we can see two knights with lances in their hands, set in a Gothic design: could this be a reproduction of a tournament?” (‘De Campagne-les-Bains a Rennes-le-Château’, Bulletin de la Société des Études Scientifiques de l’Aude. Tome XX, 1909).

Indeed, the relic could depict a conflict between opposing forces during a battle – the war between the Visigoths and the Gauls/Franks. The Visigoths were ultimately beaten by Clovis I in the Battle of Vouillé in 507. This explains why the Virgin of Lourdes stands on an upside-down “Visigothic Pillar”.

The Ceremony of the Statue of the Virgin of Lourdes was celebrated on 21 June 1891, in the presence of a Lazarist priest from the church of Notre-Dame de Marceille. Abbé Saunière's church was re-consecrated on the Feast Day of Pentecost, 6 June 1897 by Monsignor Billard, the Bishop of Carcassonne in the company of R. P. Mercier, a Lazarist priest from the Church of Notre Dame de Marceille.

The Calvary bears the inscription “Christus Vincit, Christus Regnat, Christus Imperat, Christus AOMPS Defendit (Christus Ab Omni Malo Plebem Suam Defendat), translated as Christ Conquers, He Reigns, He Commands. May He Defend His People From All Evil. These were also the words that Pope Sixtus V had engraved on the obelisk which stands in the centre of Saint Peter's Square at Rome. The words are said to be the acclamation of the Coronation Ceremony of the Holy Roman Emperors.

The “Dalle des Chevaliers” would simply be a matching version of the “Visigothic” pillar that is used as a plinth for the Virgin of Lourdes – and the reason why it's so worn is because Abbé Saunière stood on it during his religious sermons. Using the battle between the Visigoths and the Gauls/Franks as a cover for the conflict between the Church and the Republic during 19th century France, would have been necessary for Abbé Saunière because he was sanctioned as a priest in 1885 for preaching political sermons from his Pulpit against the Republic.

Therefore, there are good reasons for both the “Visigothic/Carolingian” pillar and the “Dalle des Chevaliers” to date from the period of Abbé Saunière's dispute against the French Republic 1891-1897 and not before.