A similar object is aimed at by some, in those matters which concern the New Law promulgated by Christ our Lord. For since they hold it for certain that men destitute of all religious sense are very rarely to be found, they seem to have founded on that belief a hope that the nations, although they differ among themselves in certain religious matters, will without much difficulty come to agree as brethren in professing certain doctrines, which form as it were a common basis of the spiritual life. For which reason conventions, meetings and addresses are frequently arranged by these persons, at which a large number of listeners are present, and at which all without distinction are invited to join in the discussion, both infidels of every kind, and Christians, even those who have unhappily fallen away from Christ or who with obstinacy and pertinacity deny His divine nature and mission. Certainly such attempts can nowise be approved by Catholics, founded as they are on that false opinion which considers all religions to be more or less good and praiseworthy, since they all in different ways manifest and signify that sense which is inborn in us all, and by which we are led to God and to the obedient acknowledgment of His rule. Not only are those who hold this opinion in error and deceived, but also in distorting the idea of true religion they reject it, and little by little. turn aside to naturalism and atheism, as it is called; from which it clearly follows that one who supports those who hold these theories and attempt to realize them, is altogether abandoning the divinely revealed religion. -Mortalium Animos, On Religious Unity, Pope Pius XI, 1928
“By disobedience, the Pope can separate himself from Christ despite the fact that he is head of the Church, for above all, the unity
of the Church is dependent upon its relationship with Christ. The Pope can separate himself from Christ either by disobeying the law of Christ, or by commanding something that is against the divine or natural law. By doing so, the Pope separates himself from the body of the Church because this body is itself linked to Christ by obedience. In this way, the Pope would, without doubt, fall into schism....
“He would do that if he did not observe that which the Universal Church observes in basing herself on the Tradition of the Apostles, or if he did not observe that which has been ordained for the whole world by the universal councils or by the authority of the Apostolic See. ESPECIALLY IS THIS TRUE WITH REGARD TO THE DIVINE LITURGY, as, for example, if he did not wish personally to follow the universal customs and rites of the Church.”
Cardinal Juan de Torquemada (Summa de Ecclesia 1489)
Proclaimed “Defender of the Faith” by Pope Eugene IV