How can protestants commit mortal sin if they are not aware that there is such a thing as *mortal* sin?


For a sin to be mortal, the sinner must have done something gravely wrong with full knowledge and complete consent.

The sinner must have full knowledge that the sin is mortally sinful. Protestants don’t believe that there is any difference between mortal sin and venial sin, so how could they ever have full knowledge?


Well, they can have full knowledge…but they still don’t consider it a “mortal sin”.

There are a lot of different definitions of “sin” outside of Catholicism.

If someone doesn’t believe in or define a mortal sin as you do, then of course, they don’t commit them in their own eyes.
They may in your eyes, but not in theirs.

By the same token…if you committed what you define as a mortal sin…many outside the Catholic church would not see it that way. As you know.



From hearing some Protestants you’d think they believe every sin is mortal, but can be forgiven the same way as a venial sin can.


Actually all you have to know is that a certain act is a serious matter, and freely choose to do it anyway. Whether or not you believe in the concept of “mortal sin versus venial sin” doesn’t change anything.

If a Protestant knew that adultery was a serious matter – which is something most people recognize instinctively anyways – and still decided to go ahead and commit it, he would be guilty of mortal sin. Even if he didn’t technically believe in the concept of “mortal sin” and thought all sins were equal, he still knew cheating on his wife (grave matter) was serious (full knowledge) and did it anyways. (deliberate consent) Which is the definition of mortal sin.


Protestants believe different things about sin, there isn’t one single teaching that all accept. Before I became Catholic I believed my religion was a relationship with Jesus Christ and when I sinned I hurt that relationship and needed to restore it. It was very much like my relationship with my mother in that sense. It’s not that sin would totally destroy the relationship, but that I’d wrong my Lord and needed to make it right. And I also thought that if a person was living a very sinful life it was indicative of them not having a genuine relationship with Christ. My thoughts about how sin changes our eternal destination didn’t go beyond that… I was a Christian, I had been saved by Jesus Christ and His blood was kind of like a cloak that covered my sinfulness.

I was raised Calvinist, I don’t even know if that’s calvinist theology but that’s what I believed.

So, I guess my real question is: can a person commit a mortal sin if they don’t know it is grave matter and they don’t know that grave sin can cut off our relationship with God?


Excellent. Thank you!


When the light of Jesus illuminates our soul in His presence at our particular judgement. Believe me there will be NO excuse whatsoever.

We can try to numb our conscience that screams at us, and yet we choose to do the opposite to GOD’s law. And when our conscience begins to sting us we try to silence it.
St. Peter tells us that every human being, even the pagans have the law written in our hearts. This is what our conscience is.

If the pagans will be judged based on that there will be NO excuse for the protestants OR Catholic.


They have knowledge that sin is spiritually mortal and they need to repent of all their sins. I think most Protestants do naturally understand that some sins are more grave than others, even if that isn’t what their individual denominations officially profess.


If Catholic and a Protestant both commit murder, is the Protestant less guilty because he doesn’t believe in the Catechism definitions of sin?
Both murderers are aware that murder is an evil act. Both are responsible for their actions.
Both are guilty of mortal sin even if one doesn’t believe in Catholic doctrines.


Ups! meant to write St. Paul. Silly me :smiley:


Sorry if this is offtopic, but JerryZ, if you go to the post you had written before your most recent one on this thread, there would be a button on the bottom that says “edit.” If you press it, it lets you change what you wrote in case of things like misspellings, or in your case, putting the wrong person. Just for future reference, again sorry for being offtopic


"Protestants don’t believe that there is any difference between mortal sin and venial sin"
I’m not sure that this is true for all non-catholics. Yes, there may not be a categorisation of the different sins as in catholicism but the concept is the same. What I was taught though is that a “little” sin is still sin and sometimes if we get too comfortable with them may lead to "bigger"sins.
Do you think that Protestants don’t have the knowledge that they are committng a mortal sin because they are not in the catholic church? Or maybe I am not sure what you mean by mortal sin.


This must be why they believe, once saved always saved. They don’t believe in Purgatory. Imagine thinking one would go to hell for commiting venial sins.


To be fair, I don’t think it’s all Protestants that adhere to “Once saved, always saved” – the way I see it, that tends to be more associated with perseverance of the saints in Calvinism, and then, separately, Free Grace theology, which seems to be espoused by (atleast some) Southern Baptists, among others.


God will judge.

But yes a Protestant can commit a mortal sin. They do not need to know all the “theological terms” or understanding that the Church uses.

They can know via Scripture, reason, natural law…

For example - who (in their right mind) thinks murder is not a very very serious thing.

But then again it is God who will judge them on this sin or that sin.

  1. In what does the natural moral law consist?


The natural law which is inscribed by the Creator on the heart of every person consists in a participation in the wisdom and the goodness of God. It expresses that original moral sense which enables one to discern by reason the good and the bad. It is universal and immutable and determines the basis of the duties and fundamental rights of the person as well as those of the human community and civil law.

  1. Is such a law perceived by everyone?


Because of sin the natural law is not always perceived nor is it recognized by everyone with equal clarity and immediacy.


As a former Protestant, (baptized Catholic shortly after birth, but raised and confirmed Lutheran, later going through RCIA), I can tell you what I believed.

All sins are sinful, from the small ones to the big ones, no matter how small or how big. A sin is a sin is a sin. But instead of the categorization, there was a scale, a range. If I gossiped about my friend, that is no where near the same as murder. At the same time, if lied and said I liked your new haircut to make you feel good when I really didn’t like it vs me lying about being sick to my boss so I wouldn’t have to come in to work. Each of these examples illustrated what I used to believe, in how every sin fell on a scale of “how sinful” it was, but as one other poster put it, if I asked for forgiveness, I would be forgiven, because I believed in the power of the resurrection of Jesus Christ to forgive me of all of my sins.

Now, I am Catholic.


Psalm 19
“From presumption restrain your servant and let it not rule me.
Then shall I be blameless, clean from grave sin.”

Anyone reading the bible can read that there is such a thing as grave sin.
If not, then why didn’t the bible in Ps 19 say “Then shall I be blameless, clean from sin”?
But it said “clean from grave sin” making it obvious that there is grave sin.

Peace and goodwill.


A Protestant who commits murder is committing a mortal sin. It makes no difference that their denomination may not use that phrase.

Remember, they don’t go to “confession” and confess their sins to a priest, either. Instead, they believe in confessing directly to God. Not saying this as a put-down, just stating the way it is. In that mindset, sin is sin is sin, it’s all bad, and all sins must be confessed to God. Mortal or venial, they don’t find the need to make a distinction.

On top of that, remember what Catholicism teaches. One unconfessed mortal sin condemns you to hell, while venial sins can be cleansed in purgatory. With Protestants not believing in purgatory, what need is there of the distinction in their view?


The idea that to commit a mortal sin you have to know that you are committing something called ‘mortal sin’ is entirely false. You can commit a million mortal sins without ever having heard of the phrase. The teaching that in order to commit a mortal sin we must know that we are separating ourselves from God and explicitly choose to separate ourselves from God is called the ‘fundamental option’ heresy; It is a very dangerous heresy because it leads even those who believe it innocently into sin by removing their fear of hell but without making the victim believe that, say, murder is not actually seriously wrong. The innocent victim of this heresy is not guilty of heresy but becomes guilty of many other sins which they commit, believing that they cannot go to hell or lose heaven because of them.


So, what I’m hearing is that it doesn’t matter if a person knows or agrees with the definition of mortal sin, but if they commit a sin that is very serious (not just a white lie but something like adultery) then they’ve committed mortal sin. Does that apply to Catholics, too?

The question is then, how does a person know it’s “grave matter”? Is it by their conscience or by some external rules? So an adulterer might not feel like he’s sinning or that it’s all that serious because he has a poorly formed conscience but he knows that it’s one of the commandments he’s breaking…does that make a difference? Is it only mortal sin if he believes it’s grave matter? Or does the fact that someone/society/church told him it’s very serious- is that enough to make it a mortal sin- even if he doesn’t think it’s serious? (Although a person who commits adultery and doesn’t think it’s serious is a real jerk!! lol) Maybe formication is a better example… Kids do it because they think it’s no big deal and not seriously sinful despite knowing what their parents/church teaches… Is it then mortal sin??

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