Is it permitted for Catholics to be present at, or to take part in, conventions, gatherings, meetings, or societies of non-Catholics which aim to associate together under a single agreement everyone who, in any way, lays claim to the name of Christian? In the negative! ... It is clear, therefore, why this Apostolic See has never allowed its subjects to take part in the assemblies of non-Catholics. There is one way in which the unity of Christians may be fostered, and that is by furthering the return to the one true Church of Christ for those who are separated from Her.
Pope Pius XThe true friends of the people are neither revolutionaries, nor innovators, but traditionalists.
Pope Pius XWhat will it cost you, oh Mary, to hear our prayer? What will it cost you to save us? Has not Jesus placed in your hands all the treasures of His grace and mercy? You sit crowned Queen at the right hand of your son: your dominion reaches as far as the heavens and to you are subject the earth and all creatures dwelling thereon. Your dominion reaches even down into the abyss of hell, and you alone, oh Mary, save us from the hands of Satan.
Pope Pius XI accept with sincere belief the doctrine of faith as handed down to us from the Apostles by the orthodox Fathers, always in the same sense and with the same interpretation.
Pope Pius XIs it permitted for Catholics to be present at, or to take part in, conventions, gatherings, meetings, or societies of non-Catholics which aim to associate together under a single agreement everyone who, in any way, lays claim to the name of Christian? In the negative! ... It is clear, therefore, why this Apostolic See has never allowed its subjects to take part in the assemblies of non-Catholics. There is one way in which the unity of Christians may be fostered, and that is by furthering the return to the one true Church of Christ for those who are separated from Her.
Pope Pius X