Define mortal sin vs. other types?

I was in confession & asked the priest to define mortal sin & he gave me some confusing answer that left me scratching my head. Surely, there must be an outline or definition. How am I supposed to know if I committed one??? Ugh! I’ve been a catholic all my life & the older I get, it seems the more confused I am…especially after being on this site, seeing your questions/comments - I don’t even know what you’re talking about! Twelve years of catholic school too!

This should help.

Just press control and then f on your keyboard and type in mortal sin in the search bar that will be pop up.

INQUIRINGPERSON: I’m using my phone & tried to find it on your link. It TALKS about mortal sin, but again, no definition. Thanks anyway. :frowning:

Okay, what exactly do you mean by define mortal sin? Do you mean what’s necessary for a mortal sin, or what mortal sins do to your soul?

1854 Sins are rightly evaluated according to their gravity. The distinction between mortal and venial sin, already evident in Scripture,129 became part of the tradition of the Church. It is corroborated by human experience.

1855 Mortal sin destroys charity in the heart of man by a grave violation of God’s law; it turns man away from God, who is his ultimate end and his beatitude, by preferring an inferior good to him.

Venial sin allows charity to subsist, even though it offends and wounds it.

1856 Mortal sin, by attacking the vital principle within us - that is, charity - necessitates a new initiative of God’s mercy and a conversion of heart which is normally accomplished within the setting of the sacrament of reconciliation:

When the will sets itself upon something that is of its nature incompatible with the charity that orients man toward his ultimate end, then the sin is mortal by its very object . . . whether it contradicts the love of God, such as blasphemy or perjury, or the love of neighbor, such as homicide or adultery. . . . But when the sinner's will is set upon something that of its nature involves a disorder, but is not opposed to the love of God and neighbor, such as thoughtless chatter or immoderate laughter and the like, such sins are venial.130 

1857 For a sin to be mortal, three conditions must together be met: "Mortal sin is sin whose object is grave matter and which is also committed with full knowledge and deliberate consent."131

1858 Grave matter is specified by the Ten Commandments, corresponding to the answer of Jesus to the rich young man: "Do not kill, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and your mother."132 The gravity of sins is more or less great: murder is graver than theft. One must also take into account who is wronged: violence against parents is in itself graver than violence against a stranger.

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.

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.

1861 Mortal sin is a radical possibility of human freedom, as is love itself. It results in the loss of charity and the privation of sanctifying grace, that is, of the state of grace. If it is not redeemed by repentance and God’s forgiveness, it causes exclusion from Christ’s kingdom and the eternal death of hell, for our freedom has the power to make choices for ever, with no turning back. However, although we can judge that an act is in itself a grave offense, we must entrust judgment of persons to the justice and mercy of God.

1862 One commits venial sin when, in a less serious matter, he does not observe the standard prescribed by the moral law, or when he disobeys the moral law in a grave matter, but without full knowledge or without complete consent.

1863 Venial sin weakens charity; it manifests a disordered affection for created goods; it impedes the soul’s progress in the exercise of the virtues and the practice of the moral good; it merits temporal punishment. Deliberate and unrepented venial sin disposes us little by little to commit mortal sin. However venial sin does not break the covenant with God. With God’s grace it is humanly reparable. "Venial sin does not deprive the sinner of sanctifying grace, friendship with God, charity, and consequently eternal happiness."134

While he is in the flesh, man cannot help but have at least some light sins. But do not despise these sins which we call "light": if you take them for light when you weigh them, tremble when you count them. A number of light objects makes a great mass; a number of drops fills a river; a number of grains makes a heap. What then is our hope? Above all, confession.135 

1864 "Therefore I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven."136 There are no limits to the mercy of God, but anyone who deliberately refuses to accept his mercy by repenting, rejects the forgiveness of his sins and the salvation offered by the Holy Spirit.137 Such hardness of heart can lead to final impenitence and eternal loss.

:hmmm: I will try to crack it open for you in simple terms.

Basics, there are Two (2) types of sin. Not 3 4 5 etc. Just 2

Venial and Mortal

Mortal sin in particular then how we know if it is so?

Does it break one of the 10 commandments? This is what the Church calls “grave matter

An example of grave matter would be lies. It is a sin to lie but not all lies have the same “gravity”. Some will greatly harm a person. those are Mortal. Lies that do not harm a person are at most “Venial” sin. Are you trying to protect the person from something with the lie? Could be no sin or maybe Venial.
Shurely to be safe I would confess this to my priest. Also remember that Venial sins are forgiven by attending mass but I would still confess them.

Is IT commited with “Full Knowledge”?
You know that what you are going to do is a violation of 1 or more of the 10 commandments.

Is IT commited with “Full Consent of the Will”?
So you decided to act despite the fact that you knew it was not right and proper to do so.

These are the characteristics of a “mortal sin”.
Remember that Jesus requires more from us that the Law of Moses did.
This is why merely wishing someone’s death IS a mortal sin for a Catholic. Cause you broke the 5th Commandment in your heart.

From the CCC

You shall not kill.54

You have heard that it was said to the men of old, “You shall not kill: and whoever kills shall be liable to judgment.” But I say to you that every one who is angry with his brother shall be liable to judgment.55

Hope this helps a little.

Peace :thumbsup:

Well both, really, but mainly just what defines a mortal sin?

I thank you all very much for the info - you helped greatly. If anyone has more info, please continue to post it.

Mortal sins are the only type of proper, actual sin. This is reflected in the name, “mortal”, meaning a sin that can affect death (in a final sense, as well, the second death of Hell).

They are a transgression of the laws of God, and they break the sinner’s communion with God until the sinner repents and is absolved (either by perfect contrition, sacramental confession, or possibly other ways that the Church does not pronounce on, for Christians who do not practice confession). When a mortal sin is committed, the soul is deprived of justifying grace, and it must undergo the “third justification” (a return to a state of grace after a post-baptismal sin), which is effected by the three ways mentioned above. It is generally accepted today that a sinner can undergo the third justification many times. (In the early Church, repentance was public, very long [years], and generally only allowed once after baptism. Thus some of the early Christians delayed baptism to varying degrees, into adolescence or later.)

People who will be in a state of grace at their death are called by God those who have been given the grace of perseverance: they will achieve heaven, and are larger in number than the canonized saints. (This doesn’t mean immediate access to heaven; not all people who die in a state of grace bypass purgatory, although, once in purgatory, heaven is guaranteed: there is no way from purgatory to hell, contrary to an opinion I find amongst some people in the pews that purgatory is a “sorting place” for souls.) In other words, only mortal sins can keep you out of heaven, by depriving you of justifying grace, so, while, in mortal sin, one stands before God as unrighteous, instead of standing before God clothed in the Iustitia Dei through Christ, and of Christ, and in Christ, as the sinner does when he is justified (or, as Bultmann put it in one of his moments of brilliance, “rightwised”) by and before God.

Contrary to popular opinion, the “seven deadly sins” are not sins. They are habitual inclinations to sin, but not themselves sinful. Say, someone who is affected by the “deadly sin” of lust, is not thereby a sinner: but the lust predisposes him to an actual sin in adultery, for example.

By a habit I mean not a created supernatural thing in the soul (the “habit of grace”), nor the deprivation of it (habitual inclinations to sin), which is the context the concept arose within, the mediaeval theological opinion of “created habits of grace” (which I reject, as did St Thomas). I speak of “habits” in either sense as only a psychological disposition gained by performing or avoiding the performance of a specific action, not of “habits” which are a basis for the acceptatio divina.

Other so-called “sins”, the venial sins, affect your relationship with God in no way. They are more like the “seven deadly sins”, in that venial sins (which are not sins properly so-called), are merely habits that make it more likely for a man to actually sin; they desensitize and inure him to sin; they eventually provide near occasions to sin: but they themselves are not sin. (For example, “idle talk” is considered in all older and some newer manuals a venial sin: it is not itself sinful, but can lead to sins of blasphemy, bearing false witness, etc.) Habitual performance of venial sin may harm your relationship with God, but even myriad venial sins do not destroy it.

Only mortal sin is “sin properly so-called”, that being, an action that destroys an individual’s relationship with God. Other things called “sin” or “near occasion to sin” generally are habits, vices, etc. that desensitize, habituate, and inure an individual to sin, making it more likely for him to commit an actual (mortal) sin, and, since accustomed to the sin, to make it harder for him to see the scandal in it, or the wrongness of it, and thus make it harder to repent.

“Harmatology” - the study of sin - has had thousands of books written on it; we can not define it in depth here, although I refer you to the appropriate sections in the Denzinger (look it up in the analytical index), The Fundamentals of Catholic Dogma (again, index), the Catechism of the Catholic Church (§§1846-76), and the Roman Catechism (or the Catechism of the Council of Trent), in the chapter dealing with “one baptism for the remission of sins”, which is the rubric under which it deals with harmatology.

Please note that my writing above is theologically inexact when it comes to the decrees of election, predestination, efficacious grace, etc.; I write from the human perspective of “what?”, not the Godly perspectives of “why?” and “how?”. As such, if taken literally, my above post could be spoken of as having Pelagian tendencies, because I dwell little on grace in it. I am not a Pelagian, but in fact a strict Bañezian-Thomist (i.e. “Catholic Calvinist”), but have no desire to turn my answer to the question in to a treatise on soteriology and the grace of God.

I would point out that the Church does not define “Grave Matter” based on the “10 Commandments”.
Jesus told us that His followers would not follow a law set in tablets of stone, but written in their Hearts.

Catholic Moral Theology is based on this. The church uses the term “Natural Law”.

Natural Law is not based on the 10 commandments, but rather, the 10 Commandments form a very succinct, and useful summary of the key points in Natural Law.
Remember, the 10 commandments form the beginning of the Law of Moses, from which we as christians are exempt.

Grave Matter is that which is objectively, Gravely sinful: sufficient to sever the state of friendship between the sinner and God. It is any act which rejects God’s gifts of Love and Grace.

A Mortal Sin is a sin which is committed which is:

  1. Objectively Grave
  2. Known to be Grave by the sinner (committed in full knowledge)
  3. Freely consented to by the sinner.

Therefore just because an act is objectively Grave, if the other 2 requirements are not fully present, then the actual gravity of the sin for the individual may be partially or fully lessened.

A very convienient example in this area is the often discussed issue of masturbation.
This does not appear to directly conflict with any of the 10 commandments… yet the church has allways defined it as Grave Matter.
but if we look in the Catechesim, we see a very long list of “Mitigating circumstances” which make it not a mortal sin in a huge number of scenarios… due to the reduced facculty of will of the sinner… these include:
Age and effective maturity
Force of acquired habit
distress or mental illness

2352 By masturbation is to be understood the deliberate stimulation of the genital organs in order to derive sexual pleasure. "Both the Magisterium of the Church, in the course of a constant tradition, and the moral sense of the faithful have been in no doubt and have firmly maintained that masturbation is an intrinsically and gravely disordered action."138 “The deliberate use of the sexual faculty, for whatever reason, outside of marriage is essentially contrary to its purpose.” For here sexual pleasure is sought outside of "the sexual relationship which is demanded by the moral order and in which the total meaning of mutual self-giving and human procreation in the context of true love is achieved."139

To form an equitable judgment about the subjects’ moral responsibility and to guide pastoral action, one must take into account the affective immaturity, force of acquired habit, conditions of anxiety or other psychological or social factors that lessen, if not even reduce to a minimum, moral culpability

I have selected this particular sin, simply because the conditions under which moral culpability can be lessened are so clearly set out in the catechism. Such conditions (or similar) can easily apply to a wide range of other gravely sinful behaviours, particularly those which can be strongly habit forming.

You have received much good information on how mortal sin is “defined” but I would like to address the principle behind these definitions.
Mortal sin - being deadly - stems from the rejection of God as our Lord and King. It stems from placing other things ahead of God.
Jesus tells us to “seek first the Kingdom” and tells us that all of the Law and prophets are based on two great commandments of Love…love God above all else, and love neighbor as yourself.
So - seek this love…and implement this love and you won’t have to worry much about mortal sin.

Just a thought


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