Taken from Vatican II Exposed as Counterfeit Catholicism by Frs. Francisco and Dominic Radecki, CMRI
The Catholic Church founded by Jesus Christ is based on Divine Revelation. It is composed of two unchangeable elements, Sacred Scripture and Apostolic Tradition. St. Augustine explains:
For this is our faith, that is, the true faith, the right faith, the Catholic Faith, which comes, not from private judgement—but from the testimony of the Scriptures, not based on faltering heretical rashness, but on Apostolic Truth.
The Vatican Council of 1869-1870 in its Dogmatic Constitution Concerning the Catholic Faith infallibly declared what one must believe to be a member of the Catholic Church. The theological term used for these infallible teachings is de fide (concerning the faith).
All those things are to be believed by divine and Catholic faith which are contained in the Word of God written [Sacred Scripture] or handed down [Apostolic Tradition] and which are proposed for our belief by the Church either in a solemn definition or in its ordinary and universal teaching authority.
Pope Pius XII taught, “This Deposit of Faith our Divine Redeemer has given for authentic interpretation not to each of the faithful, not even to theologians, but only to the Teaching Authority of the Church.” Dr. Ludwig Ott explains: “By dogma in the strict sense is understood a truth immediately (formally) revealed by God which has been proposed by the Teaching Authority of the Church to be believed as such.” The [first] Vatican Council’s Dogmatic Constitution of the Church of Christ, shows the Catholic Church is not a loosely knot organization, but a divine institution based on belief.
We declare that it has been so plainly determined in its founding that any societies whatsoever that are separated from the unity of faith or from communion with this body cannot in any way be said to be a part or a member of it. And it cannot be said to be diffused and distributed among the various Christian denominations; but it is an integrated unit, entirely coherent; and, in its conspicuous unity, it shows itself an undivided and indivisible body, which is the true Mystical Body of Christ.
Catholics must believe all de fide Church dogmas. Our Lord said (in Sacred Scripture), “He who is not with me is against me.” “Not everyone who says to Me, Lord, Lord, shall enter the Kingdom of Heaven; but he who does the will of My Father in Heaven shall enter the kingdom of Heaven.”