“The Catholic Church is the Only True Church”

Bishop Bernard Fellay granted an interview to the Austrian journalist Salzburger Nachrichten on June 21, 2016. Here is a large extract in which the Superior General of the Society of St. Pius X exposes the doctrinal points that are the object of the theological discussions with Rome.
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Benedict XVI was a theologian; Francis thinks along more pastoral lines. Is this a progress for the Society of St. Pius X?
Benedict XVI paid close attention to doctrine. Francis pays more attention to persons. Perhaps he even sees doctrine as an obstacle here and there. What is very important for us is for things to developing in keeping with what is right and true. We have always considered ourselves as Catholic. If that ends up being recognized, good.
The crucial point is Vatican Council II: religious freedom, ecumenism, and collegiality of the bishops. Have there been any clarifications on these subjects? Or are they not necessary?
I think that the present position of the Holy See, in particular the Congregation for the Doctrine of the Faith, comes from the intense discussions held beginning in 2009. Many things were thus cleared up.
We do indeed have objections on the three points you mention. But today many Catholics go much farther than the texts of the Council while referring to the spirit of the Council. Rome recognizes that our position on many points is right.
What is meant by religious freedom?
Anyone who claims today that the State has nothing to do with God and no duty towards God goes against the teaching of the Church. The notion of religious freedom, if we wish to understand it correctly, means that no one can impose a religion against someone’s conscience. No one can force someone to be baptized. No one can oblige someone to do anything against his conscience.
And so the Council says that every individual is free to choose, according to his conscience, a certain religion.
Vatican Council II expressly states that men must seek the Truth and cling to it. But it denies this principle for the State: the State must grant freedom to all religions and can neither hinder nor limit any, not even the false ones. And that because of a natural right. On the contrary, the traditional Magisterium of the Church teaches that the State can tolerate false religions, but these latter can claim no natural right.
And as far as the Church goes, she has the duty, always and everywhere, to preach the Truth to men and to lead them to the Truth. The Catholic Church is the only true religion, the only one that can save men. That is why she is a missionary Church.
If someone turns to another religion, he is mistaken?
Absolutely.
What is meant by ecumenism for Christians?
If by ecumenism is meant that all Christians must return to the path of the Church, then we, too, are for ecumenism. We pray for the unity of Christians. But to believe that each person can save himself as he sees fit, there we say no, that is not the teaching of the Church. In this sense we are against ecumenism.
What is wrong with episcopal collegiality?
Pope Paul VI purposely added to the text of the Council a complementary explanatory note: no bishop can claim the right to participate in the direction of the Church if he is not with the Pope and under the Pope. The pope alone decides whether someone has anything to say on the Church with him, and who that someone is. He is the monarch. To claim that the bishops have some democratic legitimacy is absolutely false. It contradicts the teaching of the Church. But today, this point is completely ignored by most of the ecclesiastical dignitaries. (…)
(source: salzburger nachrichten – translation DICI no.338 July 1, 2016)