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What Does De Fide Mean?

Dear TIA,

In my search for understanding the Catholic Faith I am running into what I think are more modern views of what de Fide means, so I thought I would ask you where to look for this. I have a very high respect for your site, and have learned a lot here. I hope you can just direct me where to go for this information. I don’t mean to burden you too much – I know you receive a lot of emails!

So my question is: How does a Catholic know what has to be believed if the infallible ex cathedra declarations of the Pope’s isn’t all there is?

Thanks so much, and God bless you all for your fight for the Faith.

     Ave Maria,


TIA responds:

Dear N.G.,

Thank you for your kind words about our website and the consideration you have for us.

Instead of directing you to a source, we are answering your questions, which coincide with those of several others of our readers.

An important trait of the only true Church established by God is to infallibly define the revealed truth. With this authority she teaches what must be believed in order to be saved. One could say that this is a logical consequence of the very divinity of God, for if He were to allow His Church to promulgate error, then He would be promoting error, which is absurd, since God himself is the Truth. The Catholic Church is, thus, able to declare to what degree a thesis or proposition is true and, consequently, must be accepted by Catholics. The classification of these propositions can range from infallible truths to probable theses.

In cases where a proposition is undefined, Catholics are freer to lend or withhold assent according to the greater or lesser degree of the proposition's certainty.

It is because of our erring intelligence and corruptible will that God established an infallible rock upon which man’s intelligence can rely. This infallible anchor is the Catholic Church. Divinely instituted, inspired and guided by the Hold Ghost, the Holy Catholic and Apostolic Church is guaranteed the unique gift of infallibility. Faithful Catholics may err, their Prelates may go astray, even a Pope can lose his compass; notwithstanding the Catholic Church is essentially incorruptible. Those who seek the safe haven of intellectual certainty can be sure of finding harbor in her infallible doctrine.

Preliminary clarifications

Before entering the topic of the degrees of belief the truths require, let us clarify three things:
  1. The ability of declaring an infallible truth is a prerogative that belongs exclusively to the Pope. A council does not have this ability and, therefore, per se it cannot be infallible. When a council declares a truth infallible, it is doing so by an authority delegated by the Pope.

  2. The Pope is not infallible in all his acts, but solely in some very few truths that he points out as being part of the Revelation based upon Scripture and Tradition.

  3. Infallible is a quality referring to a truth, not to a document or a council. For example: the truth of Papal Infallibility is a dogma, an infallible truth. But neither the Constitution De Ecclesia in which this truth was written is infallible nor the First Vatican Council, which issued that document, is infallible. It is common to hear persons say, “the infallible Bull x” or “the infallible Council z”; these qualifications do not make sense. Infallible in the Church is quality applied only to some specific truths.
Degrees of theological certainty & required degrees of faith

Not all teachings and pronouncements of the Catholic Church are infallible. Only specific teachings, as solemnly and explicitly pronounced ex cathedra by the Pope are infallibly true and free of error. These infallible truths, insofar as they are fundamental doctrines of the Catholic Faith, are classified as De Fide. That is to say, they are essential to the Faith and demand the belief of Catholics as much as the truths of the Creed.

Outside of such infallible pronouncements, Catholics are freer to formulate their own opinions. This freedom has degrees.

Although the general classification of these truths slightly vary from author to author, an analogous hierarchy is habitually presented. Ludwig Ott, in his Fundamentals of Catholic Dogma (St. Louis: Herder, 1960, pp. 9-10) formulates the varying degrees of the truths of the Catholic Faith and the corresponding required beliefs to which we added examples, some taken from Fr. Sixtus Cartechini, here:
  1. De fide divina (truth of divine faith)

    Also known as dogma, de fide, de fide Catholica. These are the truths immediately revealed by God. They possess the highest degree of theological certainty, which is the Word of God. Belief in these truths is necessary to be Catholic. The doctrine of the Holy Trinity and the Divinity of Christ are examples of de fide divina truths.

    A de fide divina truth is reinforced by the ordinary teaching of the Church (de fide Catholica) and by an official definition of the Church (de fide definita). These two latter characteristics add more authority to a truth of de fide divina and increase the obligation of a Catholic to believe it. To deny a de fide divina truth implies heresy.

  2. De fide ecclesiastica (truth of ecclesiastical faith)

    These truths are infallible, although not contained in Revelation. They were promulgated by the sole authority of the Church. An example of de fide ecclesiastica truth is the lawfulness of communion under one kind. These truths oblige Catholics as much as the revealed dogmas. To deny them implies heresy against the ecclesiastical faith.

  3. Sententia fidei proxima (proposition close to the Faith)

    These propositions are generally regarded by theologians as truths of Revelation, but not yet defined by the Church. An example of a fidei proxima truth is that Christ possessed the Beatific Vision throughout His life on earth, which has not yet been declared a dogma. The denial of these truths is classified as close to error and implies mortal sin indirectly against the Faith.

  4. Sententia communis (common opinion)

    Also known as theologically certain. A sententia communis is a common teaching of the Church although technically it belongs to the field of free opinions. It is a proposition generally accepted and agreed upon by theologians, as, for example, the true and strict causality of the Sacraments. To defy these teachings is temerarious and usually implies mortal sin.

  5. Sententia ad fidem pertinens (proposition connected to the Faith)

    This is a secure theological conclusion linked to other truths of Revelation, but not defined by the Church. Its certainty is guaranteed by its intrinsic connection with a doctrine of Revelation. An example of a an ad fidem pertinens proposition is monogenism, the belief that all the races of mankind originated from our first parents Adam and Eve. A Catholic is not bound to accept it under penalty of sin, but reveals the hue of Modernism or Progressivism if he does not.

  6. Sententia probabilis (probable proposition)

    A proposition of this type – also called more probable (probabilior) or well founded (bene fundata) – is a pious belief well established in Scriptures, Tradition or reason. For example: the tradition that Elias and Enoch did not die and will return at the end times falls in this category. Catholics are not obliged to believe these propositions. There is no sanction against those who disbelieve them.
This is the wise hierarchy the Church has established for the various types of truths and propositions she teaches to her faithful and the corresponding degrees of obedience they require.

We hope this presentation will be useful to you.


     TIA correspondence desk


Blason de Charlemagne
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Posted January 19, 2016


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