What’s the definition of heresy?

Can one commit Heresy by disagreeing with a revealed truth that is not de fide? E.g one disagrees with a Sent. fidei proxima, revealed truth?


Disagreeing with a belief that is standard but not infallibly defined would render that belief heterodox as opposed to either orthodox or heretical


I believe heresy also involves refusal to accept correction. I.e., a person could misunderstand what the Church’s teaching is, but if they refuse to accept a correction of their understanding, then they are in danger of falling into heresy.



From the CCC article 2089:

"*Heresy *is the obstinate post-baptismal denial of some truth which must be believed with divine and catholic faith, or it is likewise an obstinate doubt concerning the same;


Thanks but what does a truth that must be believed constitute?


We trust the Church to inform us of those things. Like those expessed in the Catechism of the Catholic Church.


Could you be more specific?


Wow, I just answered this on another forum! Here’s what I said:

#1, in order to be culpable of heresy, one must be aware of the trueness of the Catholic faith from which they depart doctrinally. Traditionally, you can see a good definition from Thomas Aquinas:
*The heretical tenets may be adhered to from involuntary causes: inculpable ignorance of the true creed, erroneous judgment, imperfect apprehension and comprehension of dogmas. In none of these does the will play an appreciable part, wherefore, one of the necessary conditions of sinfulness–free choice–is wanting and such heresy is merely subjective or material.*In other words, if you are honest in not understanding the Catholic faith as the true faith, you are not guilty of heresy.

Also from Catholic Answers: *A person who is ready to be corrected or who is unaware that what he has been saying is against Church teaching is not a heretic.*So if you honestly don’t recognize the Catholic Church as THE Church in the first place, you cannot be guilty of heresy against it.

#2, the Church by no means teaches non-Catholics are outside the realm of salvation. From the Catechism:
CCC#847* Those who, through no fault of their own, do not know the Gospel of Christ or his Church, but who nevertheless seek God with a sincere heart, and, moved by grace, try in their actions to do his will as they know it through the dictates of their conscience - those too may achieve eternal salvation.*So again, if you are sincere in not recognizing the Catholic Church as the Church Christ established and sincerely strive for truth, you too, can be saved.


Is a dogma something that only has a de fide level of revealed truth?


This is from The Catechism of the Catholic Church:

The dogmas of the faith
88 The Church’s Magisterium exercises the authority it holds from Christ to the fullest extent when it defines dogmas, that is, when it proposes, in a form obliging the Christian people to an irrevocable adherence of faith, truths contained in divine Revelation or also when it proposes, in a definitive way, truths having a necessary connection with these.
89 There is an organic connection between our spiritual life and the dogmas. Dogmas are lights along the path of faith; they illuminate it and make it secure. Conversely, if our life is upright, our intellect and heart will be open to welcome the light shed by the dogmas of faith.
90 The mutual connections between dogmas, and their coherence, can be found in the whole of the Revelation of the mystery of Christ. “In Catholic doctrine there exists an order or hierarchy of truths, since they vary in their relation to the foundation of the Christian faith.”

Does this address your question?


Heresy is just when someone loses an argument.


For your reading pleasure, a Christian science fiction continuing story taling place in the 23rd century far, far away fighting the spiritual poison of heresy and dangerous mind control cults in our galaxy.


After battling pirates in space we will liberate a planet (Stalintura) from a tyrannical atheist cult that forbids any worship of God.

Join us there. :thumbsup:


DISCLAIMER: The views and opinions expressed in these forums do not necessarily reflect those of Catholic Answers. For official apologetics resources please visit