Does the Church teach that one can't definitively distinguish between a venial sin and a mortal sin?

I’ve heard it on these forums before that one should confess ALL sin because one doesn’t know for sure if a sin truly is only venial instead of mortal.

Does the Church teach that one can’t definitively distinguish a venial sin from a mortal sin?

If so, where does it say that?

The closest I could find is the Baltimore Catechism saying it is good to confess venial sins become Sometimes it’s hard to distinguish, not all the time.

I’m not sure how one could entertain the possibility they committed a mortal sin if they are consciously aware of only semi-deliberately saying an idle word.

The Church definitively teaches the difference between mortal and venial sin, so we can discern the difference.

However, confessing and bringing to confession might be two different things.

My confessor and spiritual advisor taught me that if something is weighing heavily on my mind, heart, or conscience, bring that to the confessional.

And I might add, that on occasion, I have brought these concerns to confession only to be told that they were not sins, mortal or venial, at all. But, even if they are venial, it is mentally and spiritually refreshing to bring them to the Sacrament, and never have I not have venial sins not absolved because they were not grave enough.

Rejoice in the mercy of the Lord!

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The Church gives criteria for judging whether something is a mortal sin: grave matter, full knowledge, and deliberate consent. In other words, you can’t accidentally commit a mortal sin, you have to know you’re doing it and choose to do it anyway.

Where I think the confusion may come in is that someone else can’t judge whether you have committed a mortal sin.I often see threads here where someone describes what they’ve done and will get the response “that’s a mortal sin. You need to go to confession.” But without knowing how much knowledge and choice you had in the matter, an outsider can’t make that determination.

If you have questions about whether something was a mortal sin you can discuss it with your confessor who is in a situation to help you develop your conscience.

This is similar to your last question so the answer is similar. I have a well formed conscience and I distinguish which sins are mortal. I do this with 100 percent certainty.

I’ve heard it on these forums before that one should confess ALL sin

You are on a anonymous forum and could be getting advice from a 14 year old kid. Just ask your priest.

If you feel you can trust me, why I do not know, I will tell you the above is very confused and mistaken.

The only things we “should” confess are “grave sins”.
Just search the CCC, why would you go to Baltimore…its obsolete, was never a Magisterial Catechism and uses arcane language that will set you wrong.

Grave sin is not the same as mortal sin.

You also seem to be more concerned more about distinguishing gravity rather than culpability?
Is that correct?

If so the correct language is, can we distinguish grave matter from light matter?

Yes we can. Grave matter is specified by the Commandments. Some matters are ambiguous. For example stealing and lying. If the amount is trivial the matter is light.

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No. I meant culpability.

Can we distinguish when something is only semi-consent rather than full consent and vice versa.?

Ok, you werent very clear then. Venial versus mortal sin is more about the gravity of the matter.
Variable culpabilty can range from something being mortal sin to no sin at all. The acts of course remain disordered regardless of level of culpability.

So look up the Catechism re what if says about mitigating conditions re masturbation.
Also look at AL, somewhere between 297 to 305.
In the end only moral certainty can be had by ourselves…though priestly counsel can help.

In the end it doesnt matter.
We are to confess all grave sins we are conscious of.
A grave sin is a disordered act involving objective grave matter.

Acts of light matter can never in themselves be mortal sins…only venial. Though we need not confess venial sins we are of course counselled to do so.

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