Is there an offense which is ALWAYS mortally sinful by the nature of the act alone?

A recent thread asked about “grave sin.” I responded that ANY sin could be “grave” if given sufficient circumstances, but that there is no such thing as an offense (by the very nature of the offense itself) which is ALWAYS culpable of mortal sin.

Respected Forum member “steve b” objected to my (second) position, and suggested a number of offenses which (as far as I could tell) he considered “automatically” mortally sinful.

My position is that NO sin is mortally culpable unless the sinner (at the time of the offense) has perfectly formed knowledge (of the sinful nature of the act) and perfectly formed intent (to commit the sin as an act of free will, without external compulsion).

Am I wrong? Is there an offense which is always sinful by the nature of the act itself, without regard to knowledge and intent?

This question has nothing to do with acts which incur a latae sententiae (automatic) excommunication. An excommunication is a judicial procedure, not a doctrinal procedure. A person may incur a latae sententiae but remain in a State of Grace.

Hi david,

I would say it is constant rejection of the Holy Spirit’s urge to us to repent of our sins. At some level we must be aware of sin, due to the universal presence of conscience in mankind. Thus everyone must be aware of sin. I don’t believe that perfect knowledge is necessary, at least with respect to sin en toto.

Indeed this sort of rejection may be the root of mortal sin in general, that we have some particular sin that we are unwilling to repent, which sin is grave. However, sin taken as a totally is itself grave, and unless repented, at least in part, puts a person in a situation of death of the soul ie mortal sin.

Implied full consent would also be a consequence of the fact that it is repentance for sin en toto that is being rejected.


Since the definition of a mortal sin requires three things and you postulate only one being present, then, by definition, the object of the act alone cannot constitute a mortal sin.

The CCC (1857-1862) supports your contention, although it uses (§1859) the expressions “full knowledge” (not “perfect” knowledge) and “complete consent” (not “perfect”).

It might be important for you to emphasize, if I understand you correctly, that you are not disputing the notion of “intrinsic evil” as recently outlined in Veritatis Splendor, 79-83. But even here “deliberate choice” (§79) is involved.

Aren’t you confusing grave and mortal?

As Fr of Jazz pointed out, there are three things necessary for mortal sin, and one of them is grave matter.

Hence the Church, when speaking objectively of sinful acts, uses the word “grave” rather than mortal. We can say objectively that a certain action is grave, but not that it is mortal, because we don’t know if knowledge and consent are fully present.


The act itself can yes be called “mortal sin” (grave sin/serious sin-they are synonyms) -objectively. It can be better to say “grave matter” but one can legitimately say “murder is a mortal sin” or “rape is a mortal sin” etc. Depending on ones conversation - one might though still want to emphasize that yes Y is a mortal sin -do not do it!

But in order to* commit *a mortal sin one yes also needs full knowledge and deliberate consent (there are other ways one can phrase it but that is the jist).

Such knowledge need not be even the term “mortal sin” or the theology around such - but the knowledge needs to be there - as can be the case via natural moral law (though that too can clouded in the person perhaps - for sin and culture etc can cloud things etc).

Compendium issued by Pope Benedict XVI

395. 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.
396. 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.

Jimmy Akins:

If acts are intrinsically evil, a good intention or particular circumstances can diminish their evil, but they cannot remove it. They remain “irremediably” evil acts; per se and in themselves they are not capable of being ordered to God and to the good of the person.

Between the Catechism and Veritatis Splendor, it would appear that the following items can be classed as intrinsically evil:

*]Condemning an innocent person
*]Sexual perversion
*]Any kind of homicide
*]Voluntary suicide
*]Torments inflicted on the body or mind
*]Attempts to coerce the spirit
*]Subhuman living conditions
*]Arbitrary imprisonment
*]Trafficking in women and children
*]Degrading conditions of work which treat labourers as mere instruments of profit, and not as free responsible persons

These additional intrinsically evil acts are found at
*]Embryonic Stem Cell Research
*]Homosexual “Marriage”
*]Human Cloning
*]Injustice to Foreigners
*]Injustice to Orphans and Widows
*]Using Artificial Contraception
*]War of Aggression

There could be more.

As others have said, although these acts are intrinsically evil and therefore mortal sin, the act must be a grave matter that they perform with full knowledge and consent for the acts to be fully imputable to the person. In other words, mortal sin is one thing while being guilty of mortal sin is another. Ultimately we cannot know how guilty one is of the particular evil act. Only God can judge that. The best we can do is to define grave matter and to assiduously avoid them. If we do commit one of those acts, it is always correct to confess it to the priest rather than to rely improperly on your own judgment and fail to receive reconciliation and a return to grace.

I think you are right, but I do see some forum posters that say people automatically have full knowledge for certain sins. The typical example given is murder. Everyone knows it is wrong. They don’t have to be taught this, so anyone that murders with deliberate consent automatically commits mortal sin. Full knowledge doesn’t even have to be considered. Deliberate consent still needs to be considered though for people with mental health problems or people under the influence of drugs.

The Church teaches that no one is deemed ignorant of the natural law. Full knowledge is indeed considered in the case of murder because all human beings (presumably of course with the full use of reason, which excludes children and the mentally ill) are considered to possess it. Ignorance, if pleaded, must be proven, not presumed. This leaves only the question of consent.

CCC 1860. …But no one is deemed to be ignorant of the principles of the moral law, which are written in the conscience of every man…

According to Jesus, there is only one unforgivable mortal sin.
“DRV: Matthew 12: [31] Therefore I say to you: Every sin and blasphemy shall be forgiven men, but the blasphemy of the Spirit shall not be forgiven. [32] And whosoever shall speak a word against the Son of man, it shall be forgiven him: but he that shall speak against the Holy Ghost, it shall not be forgiven him, neither in this world, nor in the world to come.
The footnotes add a bit of clarity on what this means:"* [31] The blasphemy of the Spirit: The sin here spoken of is that blasphemy, by which the Pharisees attributed the miracles of Christ, wrought by the Spirit of God, to Beelzebub the prince of devils. Now this kind of sin is usually accompanied with so much obstinacy, and such wilful opposing the Spirit of God, and the known truth, that men who are guilty of it, are seldom or never converted: and therefore are never forgiven, because they will not repent. Otherwise there is no sin, which God cannot or will not forgive to such as sincerely repent, and have recourse to the keys of the church.

[32] Nor in the world to come: From these words St. Augustine (De Civ. Dei, lib. 21, c. 13) and St. Gregory (Dialog., 4, c. 39) gather, that some sins may be remitted in the world to come; and, consequently, that there is a purgatory or a middle place.*"
It seems that this would apply to anyone that attributes true miracles performed through the power of the Holy Spirit, as coming from the devil. They would likely be sinning against the Holy Spirit, if they said it was just the work of the devil. So, we should always be extremely careful how we judge any miracles that we might be tempted to say are only ‘the work of the devil’. The miracles performed by Padré Pio and other Saints of the Church, immediately come to my mind. So, we should all be careful not to be so quick to judge them, falsely. :bigyikes:

Careful. There is a distinction between principles and precepts. CCC, 1860 mentions the former, such as synderesis, “do good and avoid evil.”

CCC, 1960 teaches: "The precepts of natural law are not perceived by everyone clearly and immediately. In the present situation sinful man needs grace and revelation so moral and religious truths may be known “by everyone with facility, with firm certainty and with no admixture of error.”

Even if everybody did have full knowledge that murder is a wrong to be avoided, that doesn’t take away the fact that full knowledge is still a necessary component for a mortal sin. More than likely we’re judging by our [post] Christian culture where we can presume most mentally-healthy people past the age of reason fully know that murder is wrong.

However, I’ve seen reports and examples of media programming in some Muslim countries showing children’s cartoons glorifying suicide bombers and presenting child heroes doing it. When one grows up in a culture dehumanizing the human beings of other faiths and teaching that kind of hatred, I’m not sure most would know or even suspect there is a universal precept that no human person should be murdered . . . at least for much of their life.

Yet what precedes #1960 and what is discribed in the middle East example, are not completely wiped out in the human soul even in those circumstances. Note numbers 1955, 1956, 1957, 1958

1954** , 1955 , 1956 ,1957 , 1958, **1959

minus of course, mental illness, mentally challenged, gun to the head, etc are exceptions to the rule.

By definition the natural law (NL) is always present in the human soul: the NL is the participation of the rational creature in the eternal law. But that’s not really the issue here since we’re discussing the mental state of individuals making moral choices.

#s1954-59 define the NL which I completely accept. They do, however, articulate an ideal description of it and, in large measure, with reference to humanity as a whole over time. No one individual all alone explicitly formulated its precepts or principles. The truths summarized in 1954-9 may or may not take shape in a given mature individual’s conscious thought and choices at any one time. The principle of synderesis would always be operative, but not necessarily consciously held.

Education is necesary to draw attention explicitly to the precepts and even existence of the natural law even though human nature and its inclinations are always present. The absence of education or its perversion, as in the Islamic states I drew attention to, has a profound effect on what a given individual will hold to be wrong and right. In time reason, external circumstances, or grace may lead a particular individual (or group) in those states to some apprehension of the NL; but that is, as is all too clearly seen of late, by no means guaranteed.

An obvious example in our culture is abortion.


I agree with that. There are acts which are always of grave matter but there are no acts which are always mortally sinful.
A mortal sin can only be committed if knowledge and intent are satisfied.

I still think you could probably make exceptions for most of these.

Like abortion when the mother’s life is in danger. I don’t believe that it is a mortal sin to abort a fetus that is going to die and kill the mother if it isn’t aborted. It’s a terrible situation but one life ending is “better” than two

One can indeed speak of acts that are “always mortal sins” – in themselves. Objectively. That is Murder is a mortal sin, adultery is a mortal sin, abortion is a mortal sin, fornication is a mortal sin. (one can also say murder is a grave matter for mortal sin…)

But when it comes to if a particular person has *“committed” *a mortal sin - yes there must be full knowledge and deliberate consent.

(though as I noted before such need not be some particular theological knowledge etc - for many things can be known via natural moral law to be very serious.)

More correctly, murder is grave matter, adultery is grave matter, abortion is grave matter. If any of these are committed with full knowledge and deliberate consent, then they become mortal sin.

One may NEVER deliberately and directly cause the completed abortion of a child. It is ALWAYS grave matter and incurs immediate EXCOMMUNICATION.

The Church specifically addresses the issue of abortion if the mother’s life is in danger.

“This principle holds good both for the mother as well as the child. Never and in no case has the Church taught that the life of the child must be preferred to that of the mother. It is erroneous to place the question with this alternative: Either the life of the child or that of the mother.** No; neither the life of the mother nor of the child may be submitted to an act of suppression. **Both for the one and the other the demand cannot be but this: To use every means to save the life of both the mother and the child.”

Pope Pius XII, Address to the Family Front Congress, November 27, 1951.

2258 "Human life is sacred because from its beginning it involves the creative action of God and it remains for ever in a special relationship with the Creator, who is its sole end. God alone is the Lord of life from its beginning until its end: no one can under any circumstance claim for himself the right directly to destroy an innocent human being."56

2261 Scripture specifies the prohibition contained in the fifth commandment: "Do not slay the innocent and the righteous."61 The deliberate murder of an innocent person is gravely contrary to the dignity of the human being, to the golden rule, and to the holiness of the Creator.** the law forbidding it is universally valid: it obliges each and everyone, always and everywhere.**

2270 Human life must be respected and protected absolutely from the moment of conception.

2272 "A person who procures a completed abortion incurs excommunication latae sententiae,"76 "by the very commission of the offense,"77 and subject to the conditions provided by Canon Law.78

Latae sententiae means that the person brings instant excommunication upon himself with his act. No solemn pronouncement need be made by the Church or a Bishop or priest, and no one else need even know about the abortion. For automatic excommunication to take place, the woman must know that she is pregnant and must freely choose abortion. At the moment the woman’s child dies, she is cut off from all the Sacraments completely, and cannot return unless she sincerely repents and makes a good confession.

Statement of Intent and Principle:
Pope Pius XII summarized the intent of the double effect when he addressed the Family Front Congress on November 27, 1951; "Both for the one and the other, the demand cannot be but this: To use every means to save the life of both the mother and the child."[13]

Pius also stated the general principle of the “double effect” on October 29, 1951, at his address to the Italian Union of Midwives. This speech is codified in the Pope’s Acta Apostilicae Sedis, 43(1951), page 855.

Article 14 of the Sacred Congregation for the Doctrine of the Faith’s Declaration on Procured Abortion (November 18, 1974) reiterates it.

The pertinent passage of this document reads; **“Deliberately we have always used the expression ‘direct attempt on the life of an innocent person,’ ‘direct killing.’ **Because if, for example, the saving of the life of the future mother, independently of her pregnant condition, should urgently require a surgical act or other therapeutic treatment which would have as an accessory consequence, in no way desired or intended, but inevitable, the death of the fetus, such an act could no longer be called a direct attempt on an innocent life. Under these conditions the operation can be lawful, like other similar medical interventions granted always that a good of high worth is concerned, such as life, and that it is not possible to postpone the operation until after the birth of the child, nor to have recourse to other efficacious remedies.”

In other words, if the woman contracts cancer and requires chemotherapy and cannot wait until the birth of the child, it may be done. If the cancer requires surgical removal of the fallopian tube before giving birth and the desire is not for abortion but for healing of the cancer, it may be done. In both cases the death of the fetus is indirectly caused and results in the natural death of the fetus.

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