Pope Pius IX, Vatican Council, Session IV, Ch. 4, confirms the Fourth Council of Constantinople (8th Ecumenical) in stating: “For the fathers of the fourth council of Constantinople, adhering to the ways of the former ones, published this solemn profession: ‘Our first salvation is to guard the rule of right faith [. . .]. And since the sentiment of our Lord Jesus Christ cannot be passed over when He says: 'Thou art Peter; and upon this rock I will build my church' [Matt. 16:18], these words which were spoken are proven true by actual results, since in the Apostolic See the Catholic religion has always been preserved untainted, and holy doctrine celebrated. Desiring, then, least of all to be separated from the faith and teaching of this [Apostolic See], We hope that We may deserve to be in the one communion which the Apostolic See proclaims,in which the solidarity of the Christian religion is whole and true’.”