Does an atheist who has an abortion committing a (mortal) sin if she firmly believes that it is not sinful in the least?

this question coming from another thread on sin and salvation

Robert Sock asked the very interesting and important question; which is still among our community without definitive answer (in the title; post 38 of the cited thread).

I argued that an abortion by an atheist may be in some cases a venial sin, even if it is a mortal sin per se. This because, if the atheist has an abortion based on the argument that anyway the foetus isn’t a human being, then her knowledge of what she is actuallly doing isn’t full.

"CCC 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.

OUr culture lives on ignorance of many of God’s commands on morals, not just the rejection of them. Many don’t know and/or by rejecting it, they never tried to know. It remains that they don’t know.

It would be different if a Catholic was to do such a thing. This would be mortal."

Still other members, based on natural law say it is a mortal sin anyway.

I then continued by saying

The moral law says it is wrong to kil. Atheists recognize that.
Mortal sin is when one has full knowledge of the immorality of a thing. BUt since the atheis may think he isn’t killing a baby, but taking out a lump of cellls, he isn’t knowing that he is killing someone. In this case the objective mortal sin becomes an actual venial sin because the atheist believes he is doing the right thing. He wouldn’t do the wrong thing. He wouldn’t kill. But for the athiest, this is not killing. He can’t know it is killing if he doesn’t see it the other way around.

What are your thoughts? This is important to many here I think.
Thank you

Clearly, 3 things are required for a mortal sin:
grave matter, full knowledge, and full consent of the will.
An abortion is grave matter, yet lacking full knowledge the atheist probably would not be committing a mortal sin.
The catch comes when someday she realizes what she has done. The anguish can be overwhelming. Thank God that Rachel’s Vineyard exists to show people the love and forgiveness of God.

I think there are many levels to this argument starting if a person wants to be an atheist so she can dispense with moral law and thereby receive a blank check for any kind of behavior.
There was a nurse who after her moral epiphany couldn’t answer the question why and how she participated in abortions and back then didn’t see anything wrong about it.
They weren’t clumps of cells in front of her and yet she went along with other people were doing. After picking through the rubble of post-war Germany, people were also asking themselves why they were swept up in such a destructive process that eventually boomeranged on them. That is the point, when the force of society is so strong that it is easier to bend to the wind that is blowing rather than oppose it.
Being aware of consequences before they happen is a function of culture, to warn those against danger to themselves and others. Prohibitions against abortion were right and proper in that they saved countless women from pain and anguish. Now they are “free” to wreck their lives.
This is indeed a deep hole to crawl out of, the effects of which are not just felt after death.
Suffering in the present alone can make a person aware of the wrongness of one’s actions. This I believe is an inbuilt moral compass that everyone had, no matter how they try to blank it out.

The sin is mortal in any case. But for the individual, knowledge and intention modify culpability. If and when said atheist matures they will know that abortion is an evil act.

It’s grave matter, true. But the sin is not mortal if full knowledge and free will are not there.

The gravity of the act does not change; morality is objective. But, yes, our culpability for it changes so that we may not die as a result. In any case, “Thou shalt not kill” means that the taking of an innocent life will always be classified as a mortal sin. Ignorance does not change that fact.

One key message I get from the Gospels is that God will judge the intention of a person more than the behavior. Abortions may seem like it’s always a mortar sin to Christians, but God judges the heart. Having been an Atheist, I truly feel that many of my “mortal sins” were not held against me due to a lack of knowledge.

Why do people keep saying things like that? I know plenty of atheists who were raised by lifelong atheists or became atheist as adults that have never, despite their years and maturity, thought of abortion as an evil act. I’m talking about people in their 30’s-40’s-50’s who are educated, own homes, have spouses, have children and even grandchildren and still do not believe in God or that a fetus is a person. A couple of them have had abortions and see nothing wrong with the act. The truth is, not everyone is going to have a moment where they “see the light”.

Do I think those atheists have committed Mortal Sin? No.They can’t commit a Mortal Sin without grave matter, full knowledge, and an act of their will. These are people who literally do not believe in the concept of sin.

If and when they mature-spiritually and morally- they will know that abortion is an evil act. They may never “see the light”, but the light still shines.

To “sin” against God you need to be in friendship with God and then abandon that friendship for some other love, and that is the mortal sin.

An atheist has abandoned any friendship with God, and that is their “mortal sin”.

They do not do any acts for God, but all their acts are for something or someone else, therefore sin, whether beneficial or hurtful to society’s norms. There is no “venial sin” category among those who are at enmity with God, I believe.

An atheist is already in condemnation, no? Why speculate whether something she did will cause condemnation?

All are accountable to obey the natural law in our hearts. This includes a grace which compels us to seek God. Seeking God will lead to the simple knowledge of a corrupt moral nature in ourselves. This person has denied the beginning of wisdom by denying God. EVERYTHING a person does who denies God is unclean. Holding the sin of abortion against them is irrelevant. They must accept God before they can see anything of moral value.

Absolute mercy is to be shown to these people. The gift of forgiveness of sins and eternal life is to be offered them without judgment.

A wise priest once said: “There are actually 8 sacraments, not 7. The 8th is ignorance. It gets more people to heaven than the other 7 combined.”

And so I think it is with atheists - and many others. They’re ignorant of their wrongdoing.

Firm hatred of God and His teachings is in itself a Mortal Sin.

Its always a tough question as to the culpability of a person who doesn’t believe in the existence of sin in the first place. I pray God has mercy on all of us, for we all can sure use it.

I do think that “not believing” and “not knowing” are two different things when it comes to the question of culpability.

“Not knowing” would honestly have to mean that a person grew up and simply was never told or instructed that abortion was killing a person. In that case I think that they would be in venial sin territory since they honestly had never been exposed to that truth, and perhaps were instructed differently.

“Not believing” it is a sin is different. It means that at some point they were TOLD that life is precious, that life begins at conception, and that abortion is killing an innocent human being. They simply heard the truth and rejected it, making a conscious choice to ignore/reject the idea and instead follow their own version of right and wrong.

In a lot of ways this seems to mirror stories in the OT where a prophet is sent to a town, he delivers God’s Word, and the people reject it, later bringing down the wrath upon themselves.

Maybe those people didn’t believe what the prophet had to say either, but it didn’t change the fact that they had, in fact, been informed and given an opportunity to repent, alter their behavior, etc. They simply chose not to.

I always pray that God’s justice will be tempered with God’s mercy in cases like those

Just my .02

I agree with you more than some others here. A person can get drunk or stoned and then commit acts he was not in control over like DUI accidents but that does not exonerate getting out of control in the first place. Being an atheist is the issue here not the behavior comes from that. But one would expect it to be amoral, at best.
Islam, by the way, is against abortion. At least they admit there is a God.

I’m sorry, AcadiANNA, it is not correct to say that firm hatred of God is a mortal sin.

As always happens on this board, there are lots of people who will line up to say “X is a mortal sin.” The Church does not say this about “hating God,” and neither should we.

2 other points in this respect:

  1. There’s a very big difference between hating God and disbelieving in God: We can’t hate what we disbelieve in. We’re talking about disbelievers, not haters.

  2. Also, we ought consider: Someone who genuinely believes in God, but hates Him, may do so because of events in one’s life that reduce one’s culpability. This is not always the case, I’m sure, but I’m also sure it does happen. Perhaps the hater watched his/her innocent child die a horrible painful death and can’t reconcile such death with a loving God. Perhaps one who lived through, say, a Nazi concentration camp, or the horrors of a North Vietnamese prison camp, might fairly be very angry at God. I think those people are worthy of mercy and understanding from people like us, rather than condemnation, and I suspect God will show them more mercy than will others in this life.

Just my $0.02.

One may know that killing babies is wrong without being a Catholic. An atheist can know, by natural law alone, that killing babies is wrong. The average seven year old knows it is wrong to kill babies, puppies, and grandma.

“Full knowledge” is not the impossible high bar that those on this thread are making it out to be.

“Not believing it’s a mortal sin” does not create invincible ignorance.

Well said


If worried about a person who is an atheist being in heaven, why not introduce them to the God known in Christ, so they might develop a saving friendship with this God.

Why are we looking to sneak people in on technicalities rather than letting them know how good this God is whom we know.

Upon finding friendship with Him, they will undoubtedly also seek to present to God gifts that are pleasing to God. to present themselves to God as a friend who is pleasing to God.

We can speculate about them here, but will God ask us, “Why didn’t you introduce me to them?”

Yes, by the natural law he may know that killing babies is wrong, but by denying the existence of the Natural Law Giver, he effectively denies that morality is even objective to begin with, in any absolute sense, which was the sin of Adam. This renders morality subjective and relative and this is what opens the door for all following sin; the natrual law becomes overridden. Nice post, BTW.

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