"Full knowledge" required for mortal sin

One of the conditions given for a sin to be mortal, along with grave matter and complete consent, is “full knowledge”. Acccording to the CCC:

…knowledge of the sinful character of the act, of its opposition to God’s law.

Does this mean full knowledge that the act is sinful, or does it mean full knowledge that the act is gravely sinful?

For instance, if someone deliberately commits perjury for a non-malicious purpose, knowing it to be sinful, but believing it to be only venially so, have they sinned mortally?

Thanks.

—Soler.

It means full knowledge that the chosen act is a serious sin. If you mistakenly and sincerely believe that a chosen act is a venial sin, when in fact it is objectively grave, then the act is an actual venial sin, with only venial culpability, but is an objective mortal sin.

Your example of perjury is not a good example, since the objective morality of any act is not determined solely by good or bad intention. Perjury ‘for a non-malicious purpose’ would stil generally be an objective mortal sin, because lying under oath makes the act of lying more serious.

Ron Conte,

Thanks.

I am aware that perjury is always grave matter, which is specifically why I used it here. I only specified “for a non-malicious purpose” to exclude the possibility of their having also sinned in some other way.

Just a couple of clarifications to focus on the important difference between “sin” and “evil” – they are not identities.

“…full and truthful knowledge that the chosen act is a serious sin…” If one thinks incorrectly that the matter is grave but it is in reality not, there is no mortal sin. The matter must be grave, in fact, not in fancy.

“… objective morality of any act is not determined solely by good or bad intention.”

Since morality is always and everywhere dependent on the state of mind of the moral agent we cannot speak of “objective morality.”

Evil, however, may be objectively determined by observing the effects of an act (but not so with sin or sanctity). The objective evil of an act is always determined by its evil effects. The Church teaches that we know intrinsically evil acts but we do not know intrinsically sinful or good acts - a good act done for a bad intention does not merit any good.

“Perjury ‘for a non-malicious purpose’ would stil [sic] generally be an objective mortal sin…”

It follows from above that the Church does not teach that there are any objective mortal sins; only objective evils. Objective evils, or intrinsic evils always and everywhere have bad effects. However, one who commits an intrinsic evil does not necessarily sin, since sin has subjective components known only to the actor and God.

Peace,
O’Malley

Hello: So Cardinal Mahony did not have full knowlegde in his depostion regarding the irish priest that he is now giving a pention to. Ray

I disagree with this portion of your post. Morality is OBJECTIVE, but culpability is SUBJECTIVE. That is to say, suicide is always gravely disordered in terms of morality (ie, it is evil), but through the state of one’s will, one may be rendered such that they are not culpable of grave/mortal sin as a result. That is to say, that while morality is objective, the level of justice demanded for violations of the objective moral law is subjective.

“…full and truthful knowledge that the chosen act is a serious sin…” .

Where is this quote from? I did a search of the Catechism and could not find such wording.

The Catechism states:

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 heart 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.

If one thinks incorrectly that the matter is grave but it is in reality not, there is no mortal sin. The matter must be grave, in fact, not in fancy

citation please.

Since morality is always and everywhere dependent on the state of mind of the moral agent we cannot speak of “objective morality.”

Yes, we can. Objective morality does exist.

It follows from above that the Church does not teach that there are any objective mortal sins; only objective evils. Objective evils, or intrinsic evils always and everywhere have bad effects. However, one who commits an intrinsic evil does not necessarily sin, since sin has subjective components known only to the actor and God.

This makes no sense to me. of course there are objective mortal sins. Are you advocating relativism?

Eh, on this line he’s correct. There is no such thing as objectively mortal sins because of the requirements of culpability. There is objectively grave matter, which deals with that which is disordered under the objective moral law, but whether or not an action falls into the realm of culpability and is therefore sinful is subjective to the circumstances and person (although the caveats for culpability are, themselves, not subjective or arbitrary).

To hand over the moral law to man’s subjective opinion, which changes with the times, instead of anchoring it in the holy will of the eternal God and His commandments, is to open wide every door to the forces of destruction. **The resulting dereliction of the eternal principles of an objective morality, **which educates conscience and ennobles every department and organization of life, is a sin against the destiny of a nation, a sin whose bitter fruit will poison future generations.

From
Mit Brennender Sorge
Encyclical on the Church and the German Reich
His Holiness Pope Pius XI
March 14, 1937

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