I don't understand the CCCs way of distinguishing a mortal sin


I sorta don’t understand it, what qualifies something as a mortal and venial sin, the catechism is never clear on it. The Holy Spirit also says to me," I am not going to condemn you if you are unsure about something being a mortal sin or not". An example, which is silly would be, asking God, is it a bad if I ask God to stop my hunger during fasting and then he says, “well Marco as long as you are sorta unsure about it then it is fine,I don’t condemn you, but when you have a moment you should look up and see if it is ok to do or not”

Is this the Holy Spirit talking? Is this Holy direction correct.


There are three requirements for something to be a mortal sin: grave matter, knowledge, and consent.

It it’s something trivial (if sin can ever be called trivial), it won’t rise to the level of a mortal sin.

Second, you have to know that it’s sinful. Sometimes you’ll hear someone say “I never knew that such-and-such was a sin and I was so surprised to find out.” In a case like that, they haven’t committed a mortal sin. Now that they know it’s a sin they meet the requirement for knowledge so they should avoid the action in the future.

Third, you have to consent to the sin. Say that today, Good Friday, you forgot that it was a day of fasting and abstinence and ate a steak for lunch. Have you committed a mortal sin? No, because you didn’t consent to it, you simply forgot it was Good Friday.

Consider the word “mortal.” It’s related to death. A mortal wound leads to someone’s death. So does a mortal sin. It’s serious! You can’t accidentally commit a mortal sin or commit one without knowing it.

If you commit a sin that’s grave matter but doesn’t rise to the level of a mortal sin, it’s probably still worth confessing and gaining absolution for it. But it’s not deadly to your soul.


Aside from what has been said above, a mortal sin is a Big Thing. Taking an innocent life, hating someone so much that you relish the thought of causing them real physical or moral harm, hating God or Jesua or the Holy Spirit, missing Mass on a Sunday or Holy Day, willful consent to any unchaste thought, desire or feeling, committing any sexual act outside marriage, etc. etc. These are just examples, read your Catechism and use these examples as a guide to what a Big Thing is.



Asking God to relieve your suffering, even self-imposed suffering from fasting, is not sinful at all, let alone mortal. Even Jesus prayed, “Let this cup pass by me.”

Beyond that, SuscipeMeDomine gave an accurate and complete answer as to what constitutes mortal sin.


Your scruples are picking at you again. Pray for release from them.

closed #6

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