sentences:  He was opposed to "Action Française", which supported establishing Catholicism as the state religion, because he believed that faith and politics should remain separate.Duval was a schoolmate of the Traditionalist Archbishop Marcel Lefebvre, and in August 1976, Duval urged him to fully submit himself to the authority of the pope.Pope Paul VI created him cardinal-priest of "S. Balbina" in the consistory of 22 February 1965.