Is there ever a time a mortal sin is not considered a mortal sin?

I’ve recently stumbled upon a thought and can’t seem to find the answer outside of what our priest has told us.

Is it possible that something always considered to be a mortal sin, is not? What if committing the mortal sin is for the sake of another person and not committing it would cause an even graver evil? (Sorry for lack of specifics here).

A priest told me the other day that one disservice the church does when talking about mortal sin, is that it always states what IS a mortal sin, but doesn’t go into the details of why. Sometimes knowing the “why”, he says, helps us to better understand the gravity of it. Otherwise, it’s not necessarily a mortal sin. I suppose out of ignorance? Or is he saying that there’s this set of streamlined rules the church teaches about mortal sin, but it’s a case-by-case basis? Obviously, someone who is not Catholic and/or doesn’t understand Catholic teaching on mortal sins is technically not in mortal sin…ignorance is bliss I suppose. But what if you fully know what the church teaches about certain sins being mortal and someone tells you it wasn’t because of your extenuating circumstances? Confusing I know.

Please pardon my ignorance in advance on this topic.

One can commit a sin that is grave matter, but lack the other conditions for mortal sins (knowledge and intent). The sin then be reduced to venial, or not a sin at all.

God Bless

By the nature of the question, no; but since you are perhaps unfamiliar with the terms you are using, as the above poster said, yes.

Mortal sin by definition is mortal. Grave sin by definition is not mortal. Grave sin committed willingly and with knowledge of its gravity is mortal sin. You can commit grave sin and not have it be mortal if you were unwillingly committing it or lacking knowledge of its wrongness, or both. But God is the final judge of these, anyways. Some we thought were venial may be mortal, some we thought mortal may be venial.

Q: Is there ever a time a mortal sin is not considered a mortal sin?

An intrinsically (in itself) gravely sinful matter is not going to cease to be gravely sinful.

However the matter is not the only aspect. In order to “commit” a grave sin (mortal sin- same thing) one needs not only the grave matter but also full knowledge and deliberate consent.

So can it happen that someone does something that was a grave matter but without the knowledge or complete consent needed to commit a grave sin? Yes.

The matter though remains “grave” it is just that the person via their innocent ignorance or their lack of deliberate consent did not commit a grave sin (mortal sin -same thing).

Grave sin = mortal sin = serious sin. They are synonyms that get swapped out for each other in documents of the Magisterium etc.

Grave matter is the term to use.

Compendium issued by Pope Benedict XVI

  1. When does one commit a mortal sin?


One commits a mortal sin when there are simultaneously present: grave matter, full knowledge, and deliberate consent. This sin destroys charity in us, deprives us of sanctifying grace, and, if unrepented, leads us to the eternal death of hell. It can be forgiven in the ordinary way by means of the sacraments of Baptism and of Penance or Reconciliation.

  1. When does one commit a venial sin?


One commits a venial sin, which is essentially different from a mortal sin, when the matter involved is less serious or, even if it is grave, when full knowledge or complete consent are absent. Venial sin does not break the covenant with God but it weakens charity and manifests a disordered affection for created goods. It impedes the progress of a soul in the exercise of the virtues and in the practice of moral good. It merits temporal punishment which purifies.

Detail from

Actually much can be known via natural law and reason etc…one does not have to know murder is called a mortal sin --to commit the mortal sin of murder…

And even if in some things they do not commit the a mortal sin due to lack of consent or innocence etc --they are still harming themselves and/or others.

(and one does not need to know “why” per se – they can know it is grave and thus commit a grave (mortal) sin-- without being able to give a theological explanation of why -that is not what is meant by “full knowledge”)

Here’s a pretty interesting thread that might aid you: :wink:

And here I thought the Original Poster (that’s you) had been long since driven off that thread. :whacky:

Glad to see you survived that avalanche.

Okay, I can’t think well without a scenario, so I’m going to make one. Let’s say you want to keep your marriage, and your spouse (I’ll make it the wife) isn’t Catholic. She will not go along with NFP and still wants relations and no children, but you know “contraception” is a mortal sin. So, what are your options?

I think in this scenario it helps to know the difference between permissible material cooperation and wrongful material cooperation and *formal *cooperation. You (hypothetically the guy) might in some cases have relations with her even if she has had some kind of implant (modern version of the pill). Depending on a lot of things, this could be permissible material cooperation. Some other actions on your part, like going out and purchasing condoms and wearing them and keeping them on, these actions are more like formal cooperation.

The Catechism has a short passage about cooperation, but it doesn’t explain expressly the two terms I have used:
**1868 **Sin is a personal act. Moreover, we have a responsibility for the sins committed by others when we cooperate in them: - by participating directly and voluntarily in them;

  • by ordering, advising, praising, or approving them;
  • by not disclosing or not hindering them when we have an obligation to do so;
  • by protecting evil-doers.
    I agree that without more training than is usually provided to a Catholic, it can be hard to know what to do in the scenario I provided.
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