This renowned theologian, meditating day and night on the law of the Lord , and his colleagues at the University of Paris, conformists guardians of dogma, could not accept the very unorthodox thesis of John XXII on the ' 'beatific vision'.

Its chapel was consecrated on 16 March 1333, in the presence of Pierre de Casa and Jeanne d'Évreux, widow of Charles IV, benefactress of the Carmelite Order.

Benoît XII, who had condemned the “beatific vision” of his predecessor as soon as he was elected, wanted to have him with him and appointed him in 1341 bishop of Vaison-la-Romaine, seat left vacant by Rathier de Miremont.

The new Sovereign Pontiff, "who loved him, knew his scholarship and revered his virtues," elevated his compatriot to the Patriarchate of Jerusalem in 1345 Pierre de Casa succeeded Elijah of Nabinal.

He bequeathed his rich library to five Carmelite convents, made donations to those of Limoges and Pernes-les-Fontaines, as for his nephew, Denis de Mazerolles, he was granted 150 florins to continue his studies.