Is it a mortal sin if the actor doesn't fully comprehend the consequences?

The Catechism has the following to say about mortal sin:

*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."131

1858 Grave matter is specified by the Ten Commandments, corresponding to the answer of Jesus to the rich young man: "Do not kill, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and your mother."132 The gravity of sins is more or less great: murder is graver than theft. One must also take into account who is wronged: violence against parents is in itself graver than violence against a stranger.

1859 Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart133 do not diminish, but rather increase, the voluntary character of a sin.

1860 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. The promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders. Sin committed through malice, by deliberate choice of evil, is the gravest.

1861 Mortal sin is a radical possibility of human freedom, as is love itself. It results in the loss of charity and the privation of sanctifying grace, that is, of the state of grace. If it is not redeemed by repentance and God’s forgiveness, it causes exclusion from Christ’s kingdom and the eternal death of hell, for our freedom has the power to make choices for ever, with no turning back. However, although we can judge that an act is in itself a grave offense, we must entrust judgment of persons to the justice and mercy of God. *

I believe the key portion of the above text as it pertains to my question is that mortal sin requires full knowledge and complete consent.

If an individual commits a grave sin, but doesn’t understand the gravity of such an act, is it still mortal?

If you believe one must understand the consequences of a grave sin in order for it to be mortal, do you think it is possible for a human to commit mortal sin? The answer to this question may seem to be an obvious yes, but do you truly believe anyone would commit such an act freely knowing the eternal consequences? I am inclined to believe grave acts are only ever committed in ignorance (the person doesn’t fully understand what they are doing) or without complete freedom. the individual, for example, may have an addiction or mental illness.

I pray in hope (but not in any certainty) that out Lord reconciles all to Himself through the cross, and that no-one is ultimately permanently separated from the love and mercy of God.

For in him all the fullness of God was pleased to dwell, and through him God was pleased to reconcile to himself all things, whether on earth or in heaven, by making peace through the blood of his cross.

One need not understand the consequences, only the fact that the act was grave. It is not necessarily the consequences that make it grave, but the fact that it is entirely opposed to the way God ordered reality.

The actual consequences of an abortion are impossible for humans to predict, for example. How can you possibly know what that child would have done? But we can know that the act itself was killing a child, and that killing a child is wrong.

As for grave acts always being committed in ignorance… well all acts are committed in at least partial ignorance of the consequences, simply because we cannot even hold all the consequences in our minds. But again, utilitarianism is false, we are not to act purely in ways that we think will bring about the best consequences, but in ways that we know to actually be in themselves in accord with God’s will.

(Mental issues like addiction can lessen our guilt for sin as well, but I don’t think we could assume that those are terribly common amongst most normal healthy people.)

I personally also hope and pray that all are reconciled to Christ in the end. I just think the chances of this happening are… slim.

This issue has been a major stumbling block and has me reconsidering Eastern Orthodoxy. I don’t understand an eternal, inescapable hell. It seems that to truly respect our free will God would have to leave the door open. Just as it is theoretically possible that someone could forever say no to God, it is also seems possible that they could always end their rebellion and submit to the will of the Father.

Person: So I am stuck in hell forever?
God: Yep
Person: Why?
God: You believed that I existed, and believed you were supposed to go to Mass, but you skipped once and didn’t repent before that car crash that sent you here.
Person: Can I apologize now?
God: Nope, sorry.
Person: But I feel remorse and I want to worship you.
God: Sorry, too late.
Person: Well, what good is it going to do to keep me in this hellish state forever when I could worship you instead?
God: It is good to respect your free will.
Person: Then why don’t you respect it now?
God: You don’t get free will in hell. Sorry.
Person: That seems like a bad thing.

Your hypothetical conversation is not at all how Catholics say it would go. I’ll try to get into that as best I can, but backing up a little bit:

I don’t think you will find Eastern Orthodoxy much different on the matter. Though I am by no means an expert, and I hope someone will correct me if I’m wrong, I think the Orthodox also believe Hell to be eternal. They do, I think, phrase it in terms of a person being in the presence of God but finding that presence abhorrent and painful because they reject God, which is different from the way that Catholics phrase it in the Catechism, but I am nearly convinced that the two views are equivalent. Likewise, so far as I understand, the Orthodox do not have a concept of mortal sin as such, but do accept that purposefully putting oneself before God in a severe enough way will, without repentance, send one to Hell.

Catholics say that Hell is separation from God, but I think we have to be slightly careful on what that does and does not mean. Warning: personal thoughts that I have so far been unable to confirm or destroy, and which could easily be wrong:

  1. Those in Hell still exist. All existence comes through and is maintained by God, so the fact that they are not annihilated means that they are not isolated completely from all things from God.

  2. (Similar to 1) Those in Hell are still loved by God (else they would not exist), and this is beyond their power to control, and so they are still connected to God by this fact though they detest it.

  3. God is omnipresent - again, existence comes through God, so a place that was completely cut off from God could not actually exist, and so there cannot be a place that is in such a way completely cut off from God.

So what then does separation mean? Well, a person is in Hell if they have totally rejected God at the time of their death. A person dies in a state where they consider themselves to be the most important thing and where they consider God to be abhorrent. They are then faced by God, and turn from Him.

I would then say that separation from God is in no way God refusing to “allow us in to heaven,” or God refusing from that point onwards to accept our repentance.

Rather we separate ourselves from God by seeing Him and rejecting all that He offers. In seeing the truth and in our wretched state deciding that it is horrible, we would turn our backs on all offers of Grace that God may decide to extend, because with the clarity of the damned we know that Grace comes from God and leads us away from ourselves and to a position subservient to Him. Which we cannot abide. Therefore we refuse. So it is not so much God refusing us, as us refusing Him: separation is our refusal to join in communion, not God locking us in a box.

So, the actual judgement conversation of the Damned:
God: Hi.
**Person: **GAAAHHHHH!!! (flees in terror and loathing, refusing ever to look back)
God: Dang it, there goes another one.

As C.S. Lewis says, Hell is locked from the inside.

Here is my issue. If Hell is locked from the inside, why is it permanent? Why can’t people have the potential to leave? C.S. Lewis and Eastern Orthodoxy affirm Hell, but don’t say it is absolute, set in stone, final. It definitely can be, but they make no declaration that once a person is in Hell there is no way out. According to Lewis, if someone leaves their state of torment it was only purgatory, but if they remain in it forever it is hell.

Note the terms “mortal sin”, “grave sin” and “serious sin”

Are synonyms.

Sometimes one can get the impression that such is a distinction or some may mis-speak regarding such. But they are synonyms.

What is oftne meant was one can do something that is a “grave matter” but without the needed knowledge and consent --and thus it be a venial sin.

One can say such and such is a mortal sin (grave sin) but due to the lack of the needed knowledge or complete consent I did not commit a Mortal (grave) sin.

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.

Catechism notes:

1859 Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart133 do not diminish, but rather increase, the voluntary character of a sin.

1860 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. The promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders. Sin committed through malice, by deliberate choice of evil, is the gravest.

Because to go to Hell is reject God and all the graces He offers you completely, and humans can only repent if they accept and cooperate with the graces God gives us. Repentance does not initiate within us and we are not capable of doing it ourselves.

Recall that the only unforgivable sin is to blaspheme against the Holy Spirit (Mk 3:28-30ish) - to completely reject God and all that God offers. Those in Hell are those that do that - at death they are in such a state that upon seeing God, they want nothing to do with Him and won’t even accept the grace to repent and accept salvation.

I’ve never heard C.S. Lewis say what you said about purgatory before, the sort of near equivalence between it and Hell. Now, C.S. Lewis, as brilliant as he was, and as much as I wish he had become Catholic, was not Catholic so it is possible that he said something on the matter that Catholics would simply say is wrong, but most of what I’ve read of his on the subject makes sense. Including what he said here (with the caveat that I believe he had a historical misunderstanding indicated on the linked page in a portion I did not quote):

There [in purgatory], if I remember it [Newman’s view (dream?) that he’s agreeing with] rightly, the saved soul, at the very foot of the throne, begs to be taken away and cleansed. It cannot bear for a moment longer ‘With its darkness to affront that light’. Religion has claimed Purgatory.

Our souls demand Purgatory, don’t they? Would it not break the heart if God said to us, ‘It is true, my son, that your breath smells and your rags drip with mud and slime, but we are charitable here and no one will upbraid you with these things, nor draw away from you. Enter into the joy’? Should we not reply, ‘With submission, sir, and if there is no objection, I’d rather be cleaned first.’ ‘It may hurt, you know’ - ‘Even so, sir.’

I assume that the process of purification will normally involve suffering. Partly from tradition; partly because most real good that has been done me in this life has involved it. But I don’t think the suffering is the purpose of the purgation. I can well believe that people neither much worse nor much better than I will suffer less than I or more. . . . The treatment given will be the one required, whether it hurts little or much.

My favourite image on this matter comes from the dentist’s chair. I hope that when the tooth of life is drawn and I am ‘coming round’,’ a voice will say, ‘Rinse your mouth out with this.’ This will be Purgatory. The rinsing may take longer than I can now imagine. The taste of this may be more fiery and astringent than my present sensibility could endure. But . . . it will [not] be disgusting and unhallowed."

Purgatory is for those who die seeking God, walking the road, but aren’t yet ready. Hell is for those who die fleeing from God, and who just continue to flee after death.

I am very interested in any sort of Orthodox documents I could read that say that Hell is not eternal if you know of them, by the way. I tend to think that it is likely that the Orthodox don’t have the same notions of mortal sin and purgatory and the like as Catholics because they haven’t had the same heresies to combat and so just haven’t answered the questions. The thought that the Orthodox would not think Hell eternal surprises me - though this may just be my Western reading of their doctrine.

For example, I would think that if the Orthodox view of Hell is correct, and that a person in Hell is suffering because he cannot stand God’s presence, because he wants to hide from it and cannot, because he is so twisted that the all encompassing goodness that surrounds him is actually painful - then if God offered this person the way out, this additional good offered by God would just feel like more pain and this person would turn from this also and hunch up even more.

Your question illustrates why there is considerable debate among Catholic theologians about whether it is easy or difficult to fall into mortal sin. In the past, consensus was that it is easy (VERY easy). But the tide seems to be turning.

Theologians squabble about such questions, but this is a teaching that the Church cannot infallibly pronounce. Only God can judge the heart, and know if our knowledge or consent was complete.

However, the Church CAN infallibly make the whole question completely irrelevant. It’s called Confession (preceded by, of course, Baptism).

Scottgun in another thread posted this video where Cardinal Arinze explains this very question.

What about a situation where one is coerced or forced to act and is therefore acting under duress. One could argue that he or she has the ability to not act, and are still therefore exercising their free will by choosing to act even though a threat exists. I know this is far fetched, but it sometimes happes (though not often in the US). Example:
Person receives a phone call. Unidentified person on other end says “we have your wife and will kill her if you don’t burn down this occupied school.” It is now on you to decide, do you not comply and essentially kill your wife, or comply and possibly kill a bunch of innocents in a school? Like I said, it seems far fetched, but things like this happen (usually to a lesser extent, I just picked something huge like this to show the severity of the moral dilemma) in other parts of the world all the time.
So here someone understands the consequesces but has to pick between the lesser of two evils (cliche I know).:shrug:

By definition coercion means you do not have freewill.

We are all unintentionally ignorant of many things. That’s because we aren’t born knowing everything about everything. However, re: sin, we are already programmed by God to be disposed to the moral law. #1860 above. Therefore, we are not deemed ignorant of that. Therefore, once someone knows what sin is, and particularly sins that are gravely wrong, then one is no longer ignorant in that area. So when one commits that sin, they really committed that sin.

For example

Fornication is grave matter by definition. Once people are told this, are people ignorant of this? No. Does it stop people from committing that sin? No. Do people who commit it, try and argue that sin down to a misdemeanor or no big deal at all? Sure. Does that change the sin for that person? No

Adam and Eve were given a command by God. When they disobeyed, they knew immediately they did wrong and they tried to hide

Thistle, that video with Cardinal Arinze is excellent!

OP, coincidentally, in this morning’s Liturgy of the Hours, we prayed Ps. 99, and my spirit took note of verse 8: “O LORD, our God, you answered them; you were a forgiving God to them, though you punished their offenses.

The scripture referenced in the USCCB website on this particular was Numbers where Moses was deprived of seeing the Promised Land for his disobedience. We know too, that David was punished severely for his sin with Bathsheba and the murder of her husband Uriah.

Even in civil law where the person has committed a heinous crime, whether inadvertently or with full malice, there are consequences that the courts impose for the crime. How much more will God allow us to bear the consequences of our actions.

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