Questions about mortal sin

Hello, I was just wondering about mortal sin. If someone commits a mortal sin, abortion, pre marital sex or whatever it may be, and they know it is a sin BUT do not know that it is a mortal sin, are they guilty of a mortal sin? Sorry if that doesn’t make much sense but I’m very curious. Thank you!

Depends. Murder is something that the gravity of is written on the heart of man. So are some others.

Just because someone doesn’t know the terminology if mortal and venial sin doesn’t excuse it.

Let’s go right to the Catechism:
1857 For a *sin *to be mortal, three conditions must together be met: "Mortal sin is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent.
So in the case of abortion or pre-marital sex, we know that this is grave matter. If the person knows it was a sin and commits it with deliberate consent, the sin is mortal.

If the person truly knows that it is a sin but does not believe it to be mortal (for example,they don’t think it is grave matter) then it would not be a mortal sin.

In honesty, I cannot see how anyone could not think abortion or fornication is not grave matter. Did I help any?

I guess the matter of abortion wasn’t the best example, because it is the killing of a human life, no question there. But I’ll go back and use premarital sex and just explain the question better. Let’s say a teenager grew up Catholic but was never really all too informed about Catholic rules, teachings and morality besides knowing the huge sins such as rape, murder, all the stuff people gonto prison for. So they have sex outside of marriage, and they knew it wasn’t a good thing and was frowned upon in the Church, and was sin in some way but had no idea it was a potential mortal sin, or even knew what a mortal sin was for that matter. Would this make it a mortal sin? My apologies for the question, I know it’s silly and I could figure it out based on the 3 necessary factors but I would like to keep my own opinion out of it because sometimes our opinions cloud our judgements of right vs wrong and we hear what we want to hear and I don’t think mortal sins are something I want to form my own biased opinions about haha. Thank you very much!

The saints have written that even a venial sin, if committed deliberately, in full knowledge and freedom, can under certain circumstances be a mortal sin.

Committing the sin you mentioned, deliberately, can be a mortal sin

Because; God’s law is written on our hearts. It’s not necessary that you knew churches teaching on it to be culpable.

I don’t have time to look up the source in the Catechism right now, but…

If we know something is seriously wrong, but we choose not to believe that it’s serious – as in “I don’t think this is such a big deal, even though I’m pretty sure the Church thinks it IS a big deal” – that could actually increase our culpability rather than diminish it.

BUT, regardless of the tangle of thinking one’s been using, confession wipes out ALL sins. :thumbsup:

I highly recommend you read the section of the Catechism that discusses sin. It’s easy to find through a quick search for “Catechism of the Catholic Church mortal sin” or something like that. And it’s an easy read :smiley:

God bless you!

OK, let’s stick with fornication (no pun intended). Whether or not the person knew it, fornication is grave matter so that first test is met. Whether it is a venial sin or mortal rests on the other clauses:

  • Did they know it was a sin and did they engage in it deliberately?
    If the couple “had no idea it was a potential mortal sin” or even knew it was a sin it might only be venial. Note however that once someone tells them that fornication is a sin they can no longer plead ignorance. It would be best to take this to Father in confession.

I have had something similar happen where parents of my students have not attended Mass because they thought it was just something you had to do at Easter, not every week. Their missing Mass was grave matter, but they truly did not know they had to do it so it was not a mortal sin. However, once I told them (I had to show one couple the actual section in the Catechism for them to believe me) the next time they missed on purpose it was a mortal sin.

No apologies necessary. No question is silly if it helps us to understand the faith. Everyone on the forum, every Priest, every theologian has had silly questions and not known.

Ask away - and have a blessed Easter.

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