The Roman Catholic Church is the one true Church, founded by Christ. Christ revealed all the truths that we need to believe in order to be saved and He divinely authorized the Catholic Church to preserve and teach them until the end of time. These truths are revealed in the treasures of Sacred Scripture and Sacred Tradition, called the deposit of faith, and also called Divine Revelation. The Church must explain their meaning to the world, defend them against the corruption of error and apply their teaching to the lives of the faithful. One way that Holy Mother Church does this is when She defines dogmas and doctrines. Through them She explains the truths contained in the deposit of faith. Catholics MUST believe all dogmas and infallible doctrines, as will be explained below. Christ guarantees that, if we follow the Catholic Church as He established it, then we will know Him and all the truths which are necessary for our salvation. 


Dogmas represent the highest level of revealed truth as taught by the Catholic Church. Dogmas are infallible teachings, meaning they are protected from error by the Holy Spirit.

Definition of Dogmas

In the strict sense of the term, dogmas are teachings presented to the faithful for unconditional assent of faith, whose content and formulation are both definitively determined and neither can ever be altered. Each italicized word in this definition for dogmas is important and worth further examination.

  • Unconditional assent of faith means that these truths are divinely revealed and must be firmly believed and accepted with the obedience of faith. In other words, we must unconditionally and wholeheartedly believe and accept the meaning of how the Church explains the truth; this includes the words used and even the sequence of the words used to explain it. The sequence matters because this correct order can make the truth easier to understand. Catholics that obstinately doubt or deny dogmas fall under the penalty of heresy, which is a serious mortal sin and also a crime against the Church. This puts them outside of the Church; they are excommunicated by their actions (cf. canons 750-751, 1364). Excommunicated persons are not eligible to receive the Sacraments or a Catholic burial until they repent and are reconciled with the Church. Ignorance of these truths is no defense because all Catholics are required to learn what the Church teaches, believe it and live by it.
  • Content is the meaning of what God has revealed, either explicitly or implicitly, in Sacred Scripture and Sacred Tradition.
  • Formulation is the terminology or exact wording and the exact order of the words used in the definition to explain the revelation, truth or mystery of faith.
  • Definitively determined means the Church has used its authority and decided with absolute final certainty or certitude what this truth from God rightly means. The Church has removed it from debate and has made this final decision. Definitively determined truths are infallible.
  • Neither can ever be altered means that the exact wording and the exact meaning of the truth are permanently fixed and cannot be changed.

In dogmas, consequently, the meaning and the terminology of a teaching are absolutely final and the Catholic faithful MUST firmly believe them.

All dogmas that are defined or to be defined are based on what is found in the deposit of faith. For most dogmas the Church likes to have Scriptural grounds (even if only implicit), and Sacred Tradition for the definition. In addition, the Apostles and their successors may not define a truth unless it is found in the deposit of faith.

A variety of terms are used to refer to dogmas, all of which mean that the truth itself, as well as the very words chosen for expressing the truth, must be accepted as infallible and unchangeable, that is, permanently fixed as stated.

    • defined dogma
    • definitive dogma (definitive means made with absolute certitude)
    • definitive formulation
    • definitively determined
    • definitively formulated
    • divinely revealed
    • ex cathedra pronouncements
    • formally revealed truths
    • infallible dogma
    • revealed doctrines
    • revealed dogma
    • solemn declaration
    • solemn definition
    • solemnly defined
    • solemnly defined truth

As we have seen, what the Church teaches as dogma must be revealed by God in Divine Revelation. All dogmas are doctrines; but not all doctrines become dogmas. In fact, only a relatively few solemn definitions or dogmas have been made in the life of the Church. Why? Because when the Church sees that people are changing critical terminology or adulterating the meaning of some fundamental truth, She then intervenes with a solemn definition of the truth as a dogma. Dogmas are intended by the Church to emphasize, in certain circumstances, a doctrine that is absolutely fundamental if we are to understand clearly other teachings of the Church. They are foundational truths or teachings. Indeed, it is through solemnly defined dogmas that we come to grasp the content of the teaching. This is what is so crucial with dogmas: we cannot fully understand the meaning unless we accept the exact wording and the exact sequence of words or, that is to say, the definitive formulation.

A brief list of dogmas:

  1. Articles of the Creed
  2. Marian dogmas – Mary’s Immaculate Conception, Perpetual Virginity, Divine Maternity, and her Assumption
  3. Christ’s Institution of the Sacraments and Their Efficacy to Impart Grace
  4. Real Presence
  5. Sacrificial Nature of the Mass
  6. Divine Foundation of the Church
  7. Primacy and Infallibility of the Roman Pontiff
  8. Existence of Original Sin
  9. Inerrancy of Holy Scripture
  10. Existence and Eternity of Hell
  11. Existence of Purgatory

Those doctrines of the Faith that have not been drawn into question and have not necessarily been solemnly defined as dogmas are still necessary for belief. Whether the Church has proclaimed a truth of the Faith to be a dogma or an infallible doctrine (which is explained in the following paragraphs), the necessary level of belief is actually the same. The only difference is that the level of belief for dogmas is based directly on faith in the authority of the Word of God; and for doctrines the belief is based on faith in the Holy Spirit’s assistance to the Magisterium and on the Catholic doctrine of infallibility of the Magisterium (cf. Doctrinal Commentary on the Concluding Formula of the Professio Fidei 8). It is important to note that even though the necessary level of belief is the same, since dogmas are a higher level of teaching, the penalty for denial and disobedience is more severe.

Infallible Doctrines

The next level of Catholic teaching is infallible doctrines. (Infallible means that the doctrines are protected from error by the Holy Spirit.) Doctrines are infallible teachings that must be believed,just as dogmas are infallible teachings that must be believed, but these doctrines do not have the specific and exact words and sequence of words that are found in dogmas.  Only the meaning or content of the teaching is absolutely decided upon in doctrines. In addition, the teaching may be divinely revealed in Sacred Scripture or Sacred Tradition, or it may be a truth that is in some way connected to this Divine Revelation. The Church is capable of infallibly teaching certain things that are connected with Divine Revelation but that are not  divinely revealed.

Definition of Infallible Doctrine

Infallible doctrines are teachings, presented to the faithful for unconditional belief, whose content is definitively fixed, but whose formulation is not definitively fixed; the formulation is still to be determined. Each italicized word in this definition of infallible doctrines is examined below.

  • Unconditional belief means that we believe these truths unconditionally and that we firmly accept and definitively hold them. Firmly accept and definitively hold means that we steadfastly and confidently accept the teaching, and believe with absolute certainty and trust, that the Church’s teaching is true. These truths MUST be believed. The faithful cannot pick and choose what they want to believe. “Whoever denies these truths would be in a position of rejecting a truth of Catholic doctrine and would therefore no longer be in full communion with the Catholic Church” (Doctrinal Commentary on the Concluding Formula of the Professio Fidei 6). Not being in full communion means that the person is unworthy to present himself to receive Holy Communion and may be in serious mortal sin due to his actions against these truths. Ignorance of the truths of Catholic teaching can lessen the gravity of the sin but it does not remove it. The reason there is always some sin involved, even with ignorance, is that all Catholics have the obligation to seek out and learn what the Catholic Church teaches and conform their lives to it. Not to do so is a sin of presumption, implying that we are in no need of the saving truths given to us by God through His Church. All the measures taken by the Church are for the salvation of souls.
  • Content is definitively fixed means that the teaching is presented with absolute final certainty or certitude. The Church, using its authority, has decided exactly what this truth rightly means. Truths that have a fixed definitive content are infallible.
  • Formulation is not definitively fixed means that the exact words and the exact order of the words are not set, therefore, there is some leeway and it is acceptable to explain the truth of the Faith in other terms so long as the doctrine is not changed or denied.
  • Formulation is still to be determined means that it is possible that, in the future, this doctrine could be further defined by the Church by fixing the exact words and the exact order of the words, thus, raising it to a dogma.

Strictly speaking, 99% of the Church’s teachings are infallible doctrines; they have an exact or definitive teaching but without the exact wording or sequence of words found in definitive formulations. In fact, the entire Catechism of the Catholic Church is an example of this; its contents are all infallible Catholic doctrines, only some of which have been solemnly defined as dogmas. (The Catechism does not include theological opinion, which is covered under the next topic.)

Non-infallible Doctrines 

There are also non-infallible doctrines, which are called theological opinions. Theological opinions are non-infallible and have a content that is not definitively fixed which means that the content is not permanently set and the teaching can change. The teaching is said to be “reformable.” In other words, the teaching is not intended to be the last word on the matter. The core teaching is true but the individual details influenced by the circumstances at the time may need further modification. For example, the Church teaching may have a current pastoral use; it may recommend a particular course of action for a current issue, however, additional experience and study must occur before the issue would be formulated as a doctrine.

These non-infallible doctrines or theological opinions that are not fixed in meaning (the content), or in the wording and sequence of wording (the formulation), are presented to the faithful for religious submission of will and intellect. This means the willingness to submit loyally to the teaching of the Church on matters which may be changed and which also forbids the faithful from publicly contradicting the teaching. We submit our will and intellect because we believe that the Holy Spirit is guiding the Catholic Church for the good of all souls.

An illustration of this occurred during one period of Church history when a fallible doctrine or theological opinion for many great theologians was Our Lady’s Immaculate Conception. Theologians like Saint Thomas Aquinas and Saint Bonaventure held it to be a false theological opinion, though they did not deny the possibility of her Immaculate Conception being a true revealed doctrine if, at some point, the Church would so define it. Blessed John Duns Scotus held the contrary.  The view of Scotus, that Our Lady was immaculately conceived,  eventually was solemnly defined as a revealed truth and, hence, it became heresy to deny it. Generally, theological opinions are fallible doctrines, which can be held provided they do not lead to the denial of infallible doctrines, and they may even assist the Church in reaching a better formulation of infallible doctrines.

Development of Doctrine

Over the centuries, under the guidance of the Holy Spirit, the Church has come to see more meaningfully and more clearly what has always been believed and taught. The Church’s teaching remains always true and constant but truths can become more clear under the inspiration of the Holy Spirit. Thus, the Church continues to gain a deeper understanding and a greater ability to definitively determine the content and formulation of doctrines. This is called development of doctrine.

Indeed, all the truths of the Catholic Faith had been revealed by the end of the Apostolic Age, with the death of Saint John the Apostle. No further public revelation has occurred since then. However, part of Christ’s wisdom in founding the Catholic Church was to enable the Church to explain and even define in specific language the truths that God had revealed. But our understanding of the truths of the Faith involves a certain process of learning, a process that is protected by the Holy Spirit. The development of doctrine broadens the Church’s understanding of these revealed truths, always under the protection of the Holy Spirit which was guaranteed by Christ. (For Advanced Course lessons 7 & 13.)