Judging Mortal Sin

Hi friends! I just created an account. I’ve been wondering a lot lately: Is it possible to determine whether someone is in mortal sin? I’ve presented this (seemingly) simple question to many Catholics and I get all sorts of answers. Frankly after many discussions I’m now thinking that we as a Church Militant are not sure what the answer is. Some people straightforwardly say “yes”, some say “we can come to a very good guess”, some say “no, or at least not without a special dispensation of grace”. It seems to me that if the answer is yes, then we really don’t need God as judge, and there isn’t really any mystery involved in the particular or final judgment of souls. Someone could for example commit some gravely evil act and die right away, and we could just infallibly believe that s/he is off to hell? I’m very confused on this topic.

For what little it’s worth my own opinion is that human judgment is worth approximately nothing, and that human beings have no business trying to determine whether someone is in a state of grace or not. There seems to me this cloud surrounding people, this thick veil, beyond which others cannot see. But maybe I need to revisit this?

Thanks for helping me work through this!

If you’re not their confessor, no you can’t.

The most you can do is tell them that they’re in grave sin or serious sin, and you can tell them that it might very well be mortal sin, or that it’s highly likely to be mortal sin. But it is not the job of someone other than the confessor to decide whether someone is in mortal sin.

I think if you’re close enough to the person to know all the facts and have a good idea how their mind works, then you could make a reasonable guess, but that’s not the same as a certain determination, and you could still be wrong.

Although we cannot for sure determine if a person is in a state of grace or not, we can however determine enough in some cases that we would know whether or not to admonish them. For example, if your best friend is cheating on their spouse, we’re quite capable of informing them that it’s unacceptable behavior and a serious sin and that they are putting their soul in danger and should stop.

I suppose no one but God can be sure, but the best way to discern the state of your soul is in the confessional with a priest. What you want to avoid is asking “was my sin mortal?” to a bunch of random internet strangers on CAF.


For a sin to be mortal, 3 conditions must exist: grave matter, full knowledge, full consent. NOT knowledge or consent after the fact…at the time the sin was committed. Grave matter is easiest to determine. To make it simple, whenever you say to yourself, “I know this is wrong but I’m going to do it anyway, I don’t care what God thinks”, you should confess it.

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Even the confessor doesn’t. He simply discerns whether there’s contrition, and offers absolution.

:+1: Correct!

My answer is “no”. Even St Paul asserted that he couldn’t discern whether he was going to heaven. In other words, he couldn’t say “I’m in a state of mortal sin” or “I’m in a state of grace.”

As Catholics, we would say that we should get ourselves off to confession if we suspect that we might be in a state of mortal sin. At that point, it doesn’t matter: the sacrament of reconciliation absolves us of our sins, regardless whether venial or mortal.

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thank you very much for replying to me, I am sincerely grateful for it as I struggle with this question.

you wrote:

the catechism says people are presumed to know the sinful character of evil acts

Could you say what part of the catechism you’re thinking of? I couldn’t find anything quite like that. That would pretty much answer my question, but that’s precisely the sort of thing I couldn’t find anywhere. In fact in CC 1735 it states: “imputability and responsibility for an action can be diminished or even nullified by ignorance, inadvertence, duress, fear, habit, inordinate attachments, and other psychological or social factors.” But these things are exactly the sorts of things that can last for decades, so you never know what someone has been going through. For this reason i was skeptical of your statement that “when someone preservers obstinately, for decades committing grave sin, they are certainly in mortal sin”. Respectfully, that doesn’t seem certain in the slightest.

Not necessarily so. Someone who has been to confession but is mired in an addiction is less culpable of their acts than a person of sound mind. So performing the acts of the addiction may be lacking in full consent.

What it boils down to, is we just don’t know. We are not the judge of our brother. Don’t ever presume, unless you are a priest in the confessional, that you know the state of a soul, even a deceased person, until they are a canonized saint.

If I remember correctly, a person cannot even have true certainty of his own state of grace, barring special revelation; it was declared thus by a Church Council.


Also addiction doesn’t merely excuse sin. If someone is addicted to any kind of impurity for example, and they go to confession, they could be committing sacrilege and invalidating the confession. For validity, Penance requires: contrition, satisfaction, and firm purpose of amendment. This last requirement means someone vows firmly to change their life to avoid the sin, and to avoid the occasions of sin. If someone uses the confessional like a revolving door, knowing they will commit the same sin the next day, they clearly have no purpose of amendment. God always give sufficient sanctifying grace in confession to avoid mortal sin, so an addiction, unless it gravely impairs a person’s psychological state, such as certain drugs or antidepressants, does not remove the guilt of mortal sin.

Okay… is that what your confessors and psychologists have told you?

You are correct, that is a defined dogma of Trent that no one can know infallibly his state or whether he is a member of the elect (predestined to glory), without special revelation. Of course, if someone prays daily, is not conscience of any mortal sin, and fulfills the duties of their state in life, they can have a moral certainty that they will be saved, but they can never know for sure.

I have never seen a psychologist, nor do I have addictions. I am following the teaching of the Catechism on valid confession, and the sufficiency of grace. Also I take this from Aquinas’ teaching on culpability for sin. It is a dogma defined by the Council of Orange that God gives each person in a state of grace sufficient graces to avoid grave sin.

Unintentional ignorance can diminish or even remove the imputability of a grave offense. But no one is deemed to be ignorant of the principles of the moral law, which are written in the conscience of every man. (Paragraph 1860). By the way, if I ever contradict what the Church has taught, please I am completely open to correction.

Not at all, like I said I’m very grateful for a place & people to engage over this issue, so I appreciate your input.

To be honest, I did figure you meant that section of the Catechism when you first mentioned your point. That said, I’m quite stumped by the meaning of that section. Consider sections 1776-1794. These sections seem to significantly qualify what is said in the paragraph you mentioned (1860). Take this section in particular (1790):

A human being must always obey the certain judgment of his conscience. If he were deliberately to act against it, he would condemn himself. Yet it can happen that moral conscience remains in ignorance and makes erroneous judgments about acts to be performed or already committed.

This paragraph seems to throw into doubt an overly simply interpretation of 1860, as if the Church believed everyone knew the moral law backwards and forwards…

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That’s not correct. An addiction impairs a person’s freedom thus reducing their culpability for sin. If a person goes to confession intending to sin then this obviously doesn’t say much for their contrition never mind their purpose of amendment. However, that’s a world apart from someone who goes to confession, struggling with sin and knowing that it’s likely they’ll sin again even though they don’t want to. As a confessor, I find it humbling when someone comes back time and again struggling with the same sin. I definitely don’t condemn them or refuse absolution, instead I give thanks to God for a sinner who knows their need of the Lord’s mercy.


I think you are correct. We can certainly judge the objective gravity of sin that puts a soul in danger and based on that, try and help someone come to repentance, but never a sure judgment. This is explicitly in Scripture:

St. Paul:

1 Cor. 4:3 But with me it is a very small thing that I should be judged by you or by any human court. I do not even judge myself. 4 I am not aware of anything against myself, but I am not thereby acquitted. It is the Lord who judges me. 5 Therefore do not pronounce judgment before the time, before the Lord comes, who will bring to light the things now hidden in darkness and will disclose the purposes of the heart. Then every man will receive his commendation from God.

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So a divorced and remarried person who’s not a Catholic and is from a faith or a background where divorce and remarriage are okay is presumed to just be in mortal sin and know that they are? Nope.

Not Church teaching. You have no idea if they repented at the moment of death.
The Church also never, ever holds that a particular person is “damned”. The Church teaches that we do not know and that we can and should have hope for their soul.

Not Church teaching. Where are you coming up with this stuff? It appears you’re just posting a lot of your own opinions, or else someone has given you seriously wrong information which you’re now propagating.

I see the priest, Fr. Inthepew, has already done that with at least one of your points.

Saint Paul wrote:

“I am not aware of anything against myself, but I am not thereby justified [Gk., dedikaiomai ]. It is the Lord who judges me” (1 Cor. 4:4).

The standard is the intent not to sin again. I might desire to step back from my addiction, but know that I’m weak and will probably fall again. However, that wouldn’t mean that my confession is invalid.

Then all of us are in a constant state of mortal sin. We commit the same sins over and again, and we go to confession over and again.

But, that’s an erroneous opinion. That’s not how it works.

One can have moral certainty that they won’t sin in the future? No… that doesn’t hold up.

We are bound by our conscience, but it must be properly formed, and thus informed by reason and divine law. Because God created natural law, the very nature of our consciences binds us to obey it. Because of original sin, it becomes somewhat distorted, creating a need for divine revelation and divine positive law. That being said, as St. Paul makes plain, those without the law do the law written on their heart. People can err in good faith in certain moral decision, but my only point was that they will not commit mortal sin in good conscience for their whole life if they seek the truth, because God will give them the grace to accept divine revelation and to recognize their sins and culpability, leading them to contrition and repentance.

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