Mortal Sin---What is "Full Knowledge"?

i need a good definition of full and partial knowledge.
please help

Don’t over-complicate it.

Remember, atheists go to Hell, which tells us that there is no need to believe in God, nor to know that God disapproves of an action, in order to be able to commit a mortal sin.

All the person would have to know is that the action will damage his relationship with someone he loves (like, causing his wife to yell at him, for example) , if they find out that he did it, and, that he did it of his own free will.

Am I missing something or is this a 5 year old thread somebody has dug up??

Since you’re using “atheists go to hell” as a taken-for-granted premise , I would appreciate if you would support that. I don’t think it’s so clearcut.

Not to side track this thread but just wanted to point out that the reasons you suggested for watching pornography is not really moral in any sense. You might be forgetting the idea of concupiscence. Deliberately putting one-self in a position of temptation can be sinful while the temptation it-self is not.

Also, its questionable as to how you define something pornographic and say there is beauty in it. There is no beauty in pornography (since you already classified it as that). I think what you might be trying to say is artistic imagery that contains nudity. That is not considered pornography and artist will find it quiet offensive if you do categorize it that way. :smiley:

So to answer the rest of your question, observers can’t judge these type of sins that easily and as Catholics neither are we called to do so. It’s hard to judge when a lover gazes in to the others eyes as to whether it is with lust or with love as a bystander (though some following actions might reveal the true nature). Those are indeed sins that only the person who commits them can know unless you can read minds :).

God Bless :slight_smile:

My point is that knowledge of God is not necessary, for sin to take place.

I hope you do not think that atheists get to go to Heaven because they don’t know that they are offending God. Such a thing would be contrary to God’s justice.

If someone views something known to be “pornography”, it will be a mortal sin. It is possible that the moral responsibility for it is reduced because the person might be immature.

On the other hand, one can involuntarily come across pornography which wouldn’t really be a sin by it-self but may lead to sin.

You might also want to check the teachings on concupiscence by the Catholic church.

God Bless :slight_smile:

Yes, as the Catechism states

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.

God Bless :slight_smile:

True, but full knowledge is required for the sin to be mortal. I have not been able to find a clear official definition of “full knowledge”. It seems to me that “full knowledge” implies much more than “read it in passing on an internet forum.” If you know of an official definition of full knowledge in this context, I would love to see it.

I hope you do not think that atheists get to go to Heaven because they don’t know that they are offending God. Such a thing would be contrary to God’s justice.

They certainly can - see invincible ignorance. Condemnation for what amounts to honest mistakes is what would be contrary to God’s justice.

It means you know that it’s wrong, and you do it anyway. It’s not complicated. A seven year old can commit sin.

You do not require a degree in theology, nor the knowledge of God’s existence.

And where did you find this definition? If it is just your opinion, why is it any better than mine?

It’s not “just my opinion” - it’s what I was taught in my Catechism classes, and what I was told to teach in the classes that I teach. Sin is not this big complicated theological problem -all it is, is to do something that you know is wrong. We prepare children to go to First Confession when they are seven, because that’s the age at which they can know right from wrong - which is how it is that they have the ability to commit sin.

More later, gotta go. :slight_smile:

OK, cool. But I’m trying to find an official source. The Catechism doesn’t explain it. Gaudium et Spes seems to say that atheists may or may not be culpable for their unbelief, but doesn’t really go beyond that.

Sin is not this big complicated theological problem

Theologians seem to disagree. :wink:

-all it is, is to do something that you know is wrong. We prepare children to go to First Confession when they are seven, because that’s the age at which they can know right from wrong - which is how it is that they have the ability to commit sin.

More later, gotta go. :slight_smile:

But there must be a difference between “knowledge” and “full knowledge”, otherwise why would the criteria for mortal sin consistently include the word full?

This thread is ancient, so I don’t remember what all was said all those years ago, but I can give you a theologian quote, which is now available online. This question is one that has bothered me over time, which is why I know that it is hard to find the answer detailed out, except by a theologian. I will quote Germain Grisez, who is considered orthodox. You’d think if there were solid support for the definitions in official documents that he would footnote them (note, I think he published this text in the 1980’s). Instead, he refers you to what sound like various compilations and manuals in the notes. He seems to imply that it is a consensus of theologians type answer, if you read his footnotes.

[quote=The Way of the Lord Jesus Volume One]5. For a sin to be mortal, it is enough that a person who is willing to sin believe the matter to be grave. One willing to violate conscience in what he or she thinks a grave matter is guilty of the degree of moral evil willingly accepted. Similarly, a person who suspects that the matter might be grave and acts without taking reasonable care to eliminate doubt is guilty of the grave moral evil he or she suspects.
6. Sufficient reflection requires more than just awareness of what one is doing. Without this there is no human act at all. Sufficient reflection also requires awareness that the act is gravely wrong. In other words, reflection sufficient for mortal sin exists only if two conditions are met: (1) one acts in violation of one’s conscience, and (2) one’s conscience is that the matter either is grave or might be grave.
7. At the relevant time, one must actually be aware of the act’s wrongness. It is not sufficient simply that one could and should be aware, for in such a case one is primarily responsible for the failure to form conscience but is not gravely responsible for each unrecognized evil consequent upon this failure.


I have highlighted the part that most directly answers shawn robertson’s question. One needs to be aware that what one proposes to do is likely or sure to be a serious wrong.

I’d love to see something that isn’t theologian or textbook or manual based, but rather is official document based. Has anyone looked for it in something similar to the vademecum for confessors or the like?

If an atheist has a basic sense of right and wrong, and does something that he knows to be wrong, he is guilty of sin. He doesn’t have to be aware of all the theological nuances, nor does he have to believe that he has offended God.

Theologians seem to disagree. :wink:

Theologians get paid to complicate these kinds of things. :wink:

But there must be a difference between “knowledge” and “full knowledge”, otherwise why would the criteria for mortal sin consistently include the word full?

Right, and I think that’s where we get back to your example of someone glancing at something on the internet, versus being consistently taught it at home and at Church.

However, a person who has glanced at something on the internet that he had never heard of before, feels the conviction of the Holy Spirit - an uneasiness that he can’t shake off - and fails to follow through and find out, one way or the other, whether what he saw on the internet is, in fact, true, then he is failing to educate himself about moral principles, which itself is a grave sin.

If a person is thinking to himself, “Well, if I ignore these feelings, and just continue to do what I’m doing, and don’t look into it, maybe I will be covered by invincible ignorance.” The problem with that is, as soon as you become aware that you might be “invincibly ignorant” you no longer are - your ignorance has become “vincible” (curable) and you now have the duty to investigate the teaching, to find out more about it.

To take a very common example, suppose a couple has been using some form of artificial birth control since the time of their wedding, without realizing that there might be anything the matter with that. At some point, while browsing the web, one of them runs across an article talking about the Church’s teaching that artificial birth control is forbidden by the Church. There are two possible ways to react: the first is, “Well, no one in my Catholic school ever mentioned this, so it must be false,” and dismiss it without further investigation.

The second approach is to look further into the teaching, consult with a priest who is known to be faithful to the teachings of the Church, and to consult with one’s spouse, to discern whether this is in fact a serious sin, and to discern, if so, how to break the habit in a way that won’t harm the marriage.

Another example would be, the person reads an article on the web that says the celebration of Hallowe’en is forbidden to Catholics. Again, there are the same two possible reactions - first, ignore it and pretend that any uneasy feelings aren’t there. The second - investigate this with a faithful priest - and find out, of course, that there is no such teaching.

By discerning carefully, the person is now easy in his mind, and knows without any doubt that he can send his kids out trick-or-treating with no fear that he might be committing a sin. But if he had failed to investigate, then he would feel uneasy in his mind, and worry that maybe he was doing something wrong - which would take away from the joy of the celebration for both himself and his kids.

I have a huge problem with full knowledge. I may KNOW that the CC teaches that something is wrong, but if I’m being honest, I may not agree, or if I do, I may not agree that it is wrong to the DEGREE that the CC teaches. Let’s take masturbation, for example. I truly do not believe that it is grave matter. I suppose my faith is a bit weak here and I am questioning the logic of masturbation being a complete rejection of God along the lines of murder or adultery. I have read what the CC has to say on the matter, and while I agree that masturbation is certainly not good, I don’t think it warrants eternal separation from God. I feel the same way about a few other issues as well. I feel the same way about ABC (non-abortive and with serious reasons for practicing).

So I guess my question is this: if I know what the CC teaches and her reasoning behind it, but I disagree and doing so does not violate my conscience, is that full knowledge? Don’t I have to KNOW that something IS gravely wrong and choose to do it anyway (not just know that this is how the CC teaches it)?

I know I am supposed to form my conscience in accordance with church teaching, but that is a slow process and on some issues, I feel like I’m not getting there.

And please do not tell me that I just have to blindly do what the church says either. I have heard that before. My question is about full knowledge specifically.

Don’t you have to set out to offend God in a serious way and just not care?

No, I don’t think most mortal sins happen by the person setting out to offend God. They have something else on their mind as a goal, typically. God may not be on their radar at all.

I think if a non-Catholic knows that the Catholic Church teaches something is gravely wrong, then this knowledge alone is not enough to clinch that the person has full knowledge. It would be as if I knew the Reverend Moon teaches that X is very wrong. That is a big “So what?” in my book. What he says has no bearing on what is true, from my perspective.

A well-informed Catholic is likely to know both that there is such a thing as moral authority and that the existence of such authority means that submission/obedience is required. They are also likely to know that the Church teaches with authority. It is not required that they understand the “reasoning” behind a particular moral norm for the norm to have force upon them. I think in that case, though, their emotions aren’t going to be on the ball, and they may fail to help them with a clamor of, “This is a sin! :eek:Flee!” Just because you don’t experience it as a clamor doesn’t mean you don’t know better.

I can’t answer about you yourself, though. You do mention that you know you should form your conscience by Church teaching. This suggests to me that you may know some of the things in my previous paragraph. You may be on the hook.

Just in case it is relevant I’ll mention you ought to beware of our fallen nature’s tendency to rationalize something to the point where we can convince ourselves that we can do a particular action that in fact we really do know is wrong. You say you recognize it is wrong (on a venial level at least). That still means to turn tail and Flee! :slight_smile:

Thanks for the response! I wish the Church would be clearer on this issue. Sometimes I feel that the CC is just wrong about certain things…let’s face it, it has happened a time or 2, and I’m not yet at the point of complete submission to every single thing it has to say. I think this is going to be a journey for me and one I may never complete. That is where I struggle. If I honestly believe the church to be wrong, how can I be mortally sinning if I do what I think is right? I’m not deliberately going against God’s law, it’s just that my understanding of God’s law is different than that of the Church. I am still doing my best to be informed and to be obedient to God. I get very frustrated with the legalism of it all.

You do not have to “set out to offend God in a serious way and just not care”…one does not need the “intention to offend God in a serious way”…one does this whenever one “for whatever reason” chooses to do something that is a grave matter with full knowledge and complete consent.

For certain – Catholics know something IS grave matter…when the Catholic Church teaches that it is. (and of course when they know that such is the teaching…) Such is the main way of knowing.

And yes while there “can” be things that perhaps mitigate the guilt of a particular person even if they have “heard the teaching”…

I would caution anyone who is Catholic and thinks “well I disagree…so I do not have full knowledge”…to assume that they do are not gravely culpable…

We are not at liberty “as Catholics” to set aside the teachings of the Church…

We are as Catholics to conform ourselves to these teachings…

We need to “inform our conscience” with the teachings of the Church…


II. The Formation of Conscience

1783 Conscience must be informed and moral judgment enlightened. A well-formed conscience is upright and truthful. It formulates its judgments according to reason, in conformity with the true good willed by the wisdom of the Creator. the education of conscience is indispensable for human beings who are subjected to negative influences and tempted by sin to prefer their own judgment and to reject authoritative teachings.

1784 The education of the conscience is a lifelong task. From the earliest years, it awakens the child to the knowledge and practice of the interior law recognized by conscience. Prudent education teaches virtue; it prevents or cures fear, selfishness and pride, resentment arising from guilt, and feelings of complacency, born of human weakness and faults. the education of the conscience guarantees freedom and engenders peace of heart.

1785 In the formation of conscience the Word of God is the light for our path,54 we must assimilate it in faith and prayer and put it into practice. We must also examine our conscience before the Lord’s Cross. We are assisted by the gifts of the Holy Spirit, aided by the witness or advice of others and guided by the authoritative teaching of the Church.55

As Christians…

We hand ourselves over in Baptism in the “obedience of Faith” as Paul calls it…and we live the “obedience to the Truth” as Peter puts it.

We make that Great YES! (and let us renew it often!)

(If ever I had found that I had some feelings or thoughts to the contrary…they must fall…before the truth…)

We are to of course accept the teachings of the Church…it is Faith. Or in certain other things a at least give “religious submission of mind and will”…

But it is “Faith seeking understanding”…

…we may not “understand” fully …or be able to fully “feel it”…but one has Faith etc.

It is Faith…seeking understanding.

One then seeks to understand the whys…and wherefores… if one can…

Also we are to “renew our minds” as Paul tells us.

I propose prayerful the reading of the following two from Pope Benedict XVI:

Read them fully and carefully --they start out as if they have nothing to do with this…but read em to the end.

May the grace of Christ the King be with you!

That’s the end result of a habit of mortal sin, but it’s not the starting place. Most people start out in mortal sin by saying to themselves, “Could God have really meant this?” and then going against the teaching, not to deliberately offend God, but because in their personal opinion, they don’t think God could possibly be offended by it (or they decide that there would be something wrong with a God who is offended by these things).

This happens for each and every one of the Ten Commandments.

How can God be a jealous God? Jealousy is a sin. Therefore, God cannot possibly mind, if I keep idols in my home and rub their heads for good luck.

How could God possibly mind if I say a swear word when I hit my thumb with a hammer? If I say “Oh, God!” when I am startled, how can God be offended by that, if it was just a nervous reaction?

Does God really need me to be at Mass every single Sunday? Why does He care whether I sleep in or not?

God could not have possibly meant that I have to honour my parents - He knows how badly they treat me, and how unfair they are - they make me go to bed at midnight, and they give me nothing but meat and vegetables to eat! And they took my phone away when I failed Math last semester. God understands my problems, and isn’t going to mind that I sass my Mom and Dad all the time, because they have it coming to them.

When God said “thou shalt not kill” He didn’t mean that I couldn’t take my sister to have an abortion - her mental health was at risk, after all - our Dad would have yelled at her if he had found out she was pregnant.

If you love someone deeply, it’s okay to sleep with them even if you are not married to them - God couldn’t possibly mind that, because God created love, and God is love. (Of course, if she gets pregnant, I’m outta there - I have to finish school before I start having kids.)

Things in stores don’t really belong to anyone, yet, so it’s not really “stealing” if you take stuff from a store without paying for it. Besides, God understands that I needed that new video game.

Everybody was saying that about him, so I just passed it on. How was I to know it wasn’t really true? God doesn’t expect me to double check my facts every time I open my mouth - does He?

When I tell my girlfriend, why can’t you be more like Jeff’s girlfriend, I’m trying to improve her - really, it’s for her own good. It’s not that I’m jealous of Jeff, or want his girlfriend instead of mine. Why didn’t God give me a perfect girlfriend like Jeff’s girlfriend?

They have better cows next door, too … why can’t our cows be like their cows? God is so unfair to me … :shrug:


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