15 Mortal Sins Catholics Are Missing in Their Confessions

This is a wonderful article by Father David Nix. Warning ahead of time, he is very blunt when speaking about sexual sins. 

Part I

 Why Do We Need Confession and What Is Mortal Sin?

If you know Part I, you can click here to go right to Part II - 15 Mortal Sins Catholics Are Frequently Missing in Their Confessions

We are all born in original sin, meaning the status quo of even the cutest baby on earth before baptism has natural goodness but no supernatural goodness. Still, God has a plan of a supernatural beatitude planned for that baby in heaven in both body and soul. Because transmitted original sin separates us all from God, it would take a great sacrifice of a God-man to reconcile any person born in sin: God, because only a pure and blameless and boundless sacrifice can appease an infinite offense against an infinitely good God. Man, because a sacrifice of man is needed since “without the shedding of blood there is no forgiveness of sins.”—Hb 9:22. Thus, the only thing that can reconcile us sinners to God is a God-man, Jesus Christ on His cross. The merits of His Passion, Death and Resurrection are communicated first by baptism (1 Pt 3:21) and later confession of actual sins to a priest (Jn 20:22-23.)

If we have the grace of being baptized as babies or even as adults, then we have gained what is called “sanctifying grace.” The only way a Catholic can lose sanctifying grace is by committing a mortal sin. Every Catholic on the planet is either in sanctifying grace or mortal sin. There is no grey area in this matter. It’s extremely black and white: Again, every baptized Catholic on the planet is either in sanctifying grace or mortal sin. Those who die in sanctifying grace go to heaven, or heaven via Purgatory. Those who die in mortal sin go to hell. There are many sins like murder or child-abuse that most Catholics know are mortal sins. But the Popes and saints and Bible and Magisterium are Divine Revelation that make it very clear that most modern Catholics are missing some major mortal sins in their confessions. I have listed below the 15 most commonly “missed” mortal sins, not necessarily in order of gravity. I start with the sexual sins not because they are the most flashy, but simply to get them out of the way first. (I actually hate writing blog posts like this, but I care for so many lost Catholics.)

What is a venial sin and a mortal sin? 1 John 5 delineates between venial and mortal sin: “All iniquity is sin. And there is a sin unto death.”—1 Jn 5:17. A venial sin is a smaller sin that can be relieved by asking God’s forgiveness and saying an Our Father (similar to the means by which Protestants claim we are freed from sins in general, as they make no distinction between venial and mortal sins, even though it is explicit in Scripture!).  A mortal sin, however, kicks the Blessed Trinity out of our soul and the only way to regain Jesus’ friendship is through confession to a priest (Jn 20:23). What constitutes a mortal sin? First, grave deeds, but “besides grave matter, there is also required full consciousness of the gravity of the matter, along with the deliberate will to commit the sin.”—Catechism of Saint Pius X . Now, most of the emphasis over the past 50-70 years has been put on the subjective two parts of that above definition.  But even the new Catechism of the Catholic Church says of vincible (lazy) ignorance that “this ignorance can often be imputed to personal responsibility.  This is the case when a man ‘takes little trouble to find out what is true and good, or when conscience is by degrees almost blinded through the habit of committing sin.’ In such cases, the person is culpable for the evil he commits.”—CCC 1790-1791. In other words, if you’re reading this blog post, you’re responsible for knowing the below 15 sins. Even if you stop reading now, you’re still responsible before God.

The good news, however, is that with a General Confession (a lifetime confession) of all your sins, you will leave the confessional as clean and as strong as a baby on the day of its baptism. And you will feel it—immediately. The one thing greater than your ability to sin is your Heavenly Father’s ability to forgive you, so I promise you that God is powerful enough to forgive even the most serious or the most embarrassing sins that you confess. We priests have heard them all, so it’s impossible to shock us. We will not be mean to you.  Confession might seem hard, but think of the trade off: You trade 10 minutes of embarrassment for an eternity in hell that Jesus paid by being tortured for 17 hours for you from the Garden to Caipahas’ house to the scourging to the Cross. The merits of His death for you are communicated by baptism and confession. That is the trade off: that Jesus Christ paid the penalty of all the below sins. Such is his infinite mercy. So, just confess the below sins to a solid priest (namely, who will respect your conscience) because you will feel the weight of the world off your shoulders. Just believe the Church saints and doctors who I quote below on what is mortal versus venial sin. If you have any of the following sins on your heart, you need to confess them (with number, even if estimated) to avoid the fires of hell and the eternal loss of God.

Part II 

15 Mortal Sins Catholics Are Frequently Missing in Their Confessions

1. Contraception, IVF and Abortion. 

Most readers here know that abortion is murder. But many Catholics do not know that contraception (in marriage or out of marriage) is a mortal sin. Both sterilization (of the man or woman) and/or the condom (male or female) is a mortal sin. These must be confessed to enter sanctifying grace. But there is a worse contraceptive sin than even the condom or sterilization within marriage: Many Catholics do not know that the Oral Contraceptive and the IUD function half the time as a contraceptive and half the time as an abortifacient. I explained the medicine of that in this podcast here. This means that Catholic women on the Pill (and the men who sleep with them) should confess their sorrow not only for the mortal sin of contraception in marriage, but also having killed any of their own children through the use of the Pill, the shot or the birth-control implant in the arm. All of these OCs are chemically wired to first stop ovulation and then, as a back-up, to slough off the inner-lining of the uterus to eject newly formed individuals (your children!) into the toilet.  As most readers know, IVF requires you to sacrifice about 20 of your own children via both “embryo reduction” and “freezing” to get about two of them born.  Thus, IVF is literally murdering and freezing many of your children to get a few born for yourself.  God can quickly forgive the murder of children. If even a priest as intense as me will not scream at anyone in the confessional for this sin, then neither will any priest out there. Just confess it, even if you didn’t know it.

2. Masturbation and/or Pornography, before marriage or within marriage. 

Some saints have pointed out that sins which exacted physical death in the Old Covenant (Judaism) are frequently the sins that cause spiritual death in the New Testament (Catholicism.) God directly only kills a few people in the Old Testament, and Onan is one of them: “But Onan knew that the offspring would not be his. So whenever he went in to his brother’s wife he would waste the semen on the ground, so as not to give offspring to his brother. And what he did was wicked in the sight of the Lord, and He put him to death also.”—Gen 38:9-10. Thus, sterilization and masturbation and the use of the condom is a mortal sin even when no pornography is used. How about pornography without masturbation? This too is a mortal sin since Jesus said “But I say to you, that everyone who looks at a woman with lustful intent has already committed adultery with her in his heart.”—Mt 5:28.” In this vein, simply lusting after a woman or a man on the street can be mortal sin! But thankfully St. Francis De Sales (a doctor of the Church) gives us some parameters to know if we consented to such temptations (footnote 1)

3. Immodesty, Including Wearing Leggings and Short Shorts.

I could quote countless saints here, but the most succinct description is what the Mother of God said at Fatima: “Certain fashions will be introduced that will offend Our Lord very much.”—Our Lady of Fatima, 1917. What are these certain fashions? If not leggings and short shorts, then what? Strangely, many Catholic women know this quote from Fatima, but they only apply it to women who wear less than themselves. Ladies, when you hear that quote from Our Lady of Fatima that certain fashions will lead you (and the men who look at you) to hell, are you imagining some imaginary time in the year 3022 when some fashion gets worse than leggings and short shorts? What could be more revealing than something that shows every nook and cranny below your waist?  What would this magical outfit be that could be worse than that? There is nothing. Rather, let me assure you: The Mother of God very much meant that short shorts, leggings and bikinis will lead you to hell, including letting your little girls wear leggings.  If you wear these things to Mass, you should also confess sacrilege.  Or, if you don’t believe my interpretation of Mary’s words, then go for it. Wear it and let your daughters prance around Target in short-shorts and leggings.  But might I suggest Pascal’s wager for this one: If your parish priest is right and Fr. Nix is wrong on his interpretation of Fatima, then the most you have lost is a little “comfort” in avoiding leggings for believing me in an erroneous state. But if Fr. Nix is correct in his interpretation (that Mary meant nothing worse than leggings and short-shorts) then just meditate on your first 15 seconds in hell. As Fr. Z says, just meditate on your first 15 seconds in hell.  Meditate on that 7000 degree furnace for fifteen seconds and the realization that you just lost God forever because you thought leggings (again, that showed every nook and cranny of your nether-regions to every man around you) led you and countless men to hell for the sake of “comfort.” Am I using fear of hell to get you to stop wearing leggings and short shorts? Hell yes, I am.

4. Before marriage, making-out or anything more passionate than that. 

St. Thomas Aquinas writes:  “I answer that a thing is said to be a mortal works. One may sin in two ways. First, by reason of its species, and in this way a kiss, caress, or touch does not, of its very nature, imply a mortal sin, for it is possible to do such things without lustful pleasure, either as being the custom of one’s country, or on account of some obligation or reasonable cause. Secondly, a thing is said to be a mortal sin by reason of its cause: thus he who gives an alms, in order to lead someone into heresy, sins mortally on account of his corrupt intention. Now it has been stated above (FS, Q[74], A[8]), that it is a mortal sin not only to consent to the act, but also to the delectation of a mortal sin. Wherefore since fornication is a mortal sin, and much more so the other kinds of lust, it follows that in such like sins not only consent to the act but also consent to the pleasure is a mortal sin. Consequently, when these kisses and caresses are done for this delectation, it follows that they are mortal sins, and only in this way are they said to be lustful. Therefore in so far as they are lustful, they are mortal sins…”—ST II.II.154.4 c

5. In marriage, anything unnatural. 

The two greatest moral theologians of the Church, St. Thomas Aquinas and St. Alphonsus Ligouri both teach that anal sex in marriage is a mortal sin.  Even Catholic Answers once had an article explaining that any form of insertion-based oral-sex is a mortal sin—even in marriage. If you confess this sin, expect many parish priests to say, “it’s not a sin.” Then, you will say, “But St. Thomas Aquinas and St. Alphonsus Liguori both say it’s a mortal sin.” Then, your parish priest will probably say: “But they’re not infallible.” This reveals his total lack of understanding of Divine Revelation –  that so much more than ex-cathedra statements are infallible in the Catholic Church. I don’t have time to re-vamp every priest’s six years in a single blog post on mortal sins and how hundreds of Popes agree with those two saints, so please just go to a traditional priest who knows this…or…pull out a modernist priest’s favorite line: “Please just respect my conscience in confessing this!”  2

6. Homosexual Acts. 

All sexual sins (heterosexual or homosexual) are mortal sins if committed with consent. But homosexual sins are not only under the category of mortal, but under the category of mortal PLUS sins that are said to cry to God for vengeance. This means that sodomy is one of the four worst mortal sins you can commit.  There is nothing wrong with same-gender friendship, but ramming a penis in an anus is filthy and evil and violent.  That is what sodomy is.  I know there are some priests out there committing sodomy, and other priests out there not committing sodomy but celebrating those who do commit sodomy. Let me be very blunt for the sake of your soul: If you are committing homosexual sins and do not repent, confess them and try your best to stop, you will go to hell forever. I’m sorry to be blunt, but I say this because I love you, and I really believe God can forgive everyone’s sins. Everyone knows God is merciful, but He is also powerful enough to forgive such filthy sins and make you clean again. 

7. Chronic failure to catechize your kids. 

Many good mothers and fathers occasionally miss some catechetical lessons for their kids, and that is not a big deal. That is why I say it’s only a mortal sin if you had a chronic (lifetime) failure to catechize your children. So, if you fail to learn the Catholic faith and fail to teach it to your children (and I don’t mean to just Sunday Mass, I mean the fullness of the Catholic faith) then this is a mortal sin. This is especially directed at biological fathers and priests, as you are called to be the main catechizers of your families and flocks. Look, none of this is legalism. It all comes down to love: “If you love me, you will keep my commandments.”—Jn 14:15. How can your children know Jesus if you don’t teach them how to pray and meditate and pray the Rosary? The Rosary, when prayed correctly, truly introduces us to Jesus Christ so your kids will never hear this from Our Lord at the end of their lives: “Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but the one who does the will of my Father who is in heaven. On that day many will say to me, ‘Lord, Lord, did we not prophesy in your name, and cast out demons in your name, and do many mighty works in your name?’ And then will I declare to them, ‘I never knew you; depart from me, you workers of lawlessness.’”—Mt 7:21-23

8. Greatly harming someone’s reputation. 

St. Ignatius of Loyola writes, “If I reveal a hidden mortal sin of another, I sin mortally. If I reveal a hidden venial sin, I sin venially; if his defect, I manifest my own.” That means that if I gossip that my neighbor committed adultery, it puts me in mortal sin, as I have revealed a hidden mortal sin. But key to this phrase is the word “hidden” because if you reveal, for example, that your mother no longer goes to Mass or your father left the Catholic Church, these are public mortal sins. Not that they should be talked about a lot, but discussing a public mortal sin, say of a politician, where it is not good practice for the Catholic, is not mortal sin. Another exception to this is intervention. For example, if your neighbor is sexually molesting his children, you are required to call the police. If your uncle is an alcoholic, you may need to have an intervention. It is not a sin to discuss these things, but it always must be for physical safety and eternal salvation of others.  Also, be sure to avoid couching the gossip of mortal sins into prayer: “Yeah, that gal in our Bible Study really needs prayers because she keeps flirting with the priest.” Again, St. Ignatius of Loyola: “If I reveal a hidden mortal sin of another, I sin mortally.”

9. Missing Sunday Mass without good reason and/or unnecessary work on Sunday.   

It used to be that unnecessary work on a Sunday was considered to be over two hours of work.  St. John Vianney, who saw people pushing their farming carts around on Sunday. He said, “I see them pushing their carts and I see them pushing them into hell.” Could we not say that at a Wal-Mart on Sunday? “I see them pushing their carts, and I see them pushing them into hell.” Again, a caveat is in order here. There is necessary work on Sunday. For example, the medical field requires workers on Sunday: “Is it lawful on the Sabbath to do good or to do harm, to save life or to kill?”—Mark 3:4. Or, if you have a big feast for your family on Sunday, of course it may be necessary to do a couple hours of clean up. Also excepted is charity work: cleaning up your Church, or working at a soup kitchen. These are not only permitted, but even encouraged on Sundays. But all in all, we should work on Saturdays like Jews work on Fridays to get everything done. I can already hear a lot of priests reading this blog post and their response to me: “But under the new law we are free in Jesus Christ so why compare us to Old Testament Jews and the Sabbath?” My answer: “Precisely so we can be the free sons of God on Sundays with our families.”

10. Denying your workers a fair wage. 

Pope St. Pius X writes in his Catechism, “The sins that are said to cry to God for vengeance are these four: (1) Willful murder; (2) The sin of sodomy; (3) Oppression of the poor; (4) Defrauding labourers of their wages.” Those last two must be highly considered by any Catholic business owners out there. These are the four most serious sins that the Church has put forth. This is not antiquated devotionals of Fr. Nix. This is the Magisterium of the Catholic Church. Many more parts of our articulated faith and morals are infallible than just the two ex-cathedra statements.

11. Getting Drunk or High. 

I will be coming out with a podcast or blog post on drugs in the future, so let’s briefly focus on why getting drunk on alcohol is a mortal sin. Getting drunk is not a mortal sin only because it leads to doing other mortal sins (like most people say today), but also in and of it itself, drunkenness overturns the greatest natural gift given to us, our reason. The threshold to balance between buzzed and drunk for St. Alphonsus Liguori is not as difficult to meet as some might have thought: “It is certain among all authorities that for it to be the case that drunkenness to be a mortal sin it is required that it would be perfect drunkenness, namely that it would altogether deprive one of the use of reason, just as St. Thomas teaches (II IIæ q. 150, a. 2), and with all the doctors. The malice of drunkenness consists in this, that a man, wishing and knowing, deprives himself of the use of reason. St. Antoninus teaches the same thing in p. 2 tit. 6, c. 3 § 1. This is why one would not sin mortally that did not altogether lose the use of reason from drinking wine, even if the mind were disturbed, but not so much that he were not able to discern between good and evil, as the authors commonly say…{It is] the common opinion to teach that drunkenness is not a mortal sin if it would deprive one from reason for only a brief period.”—St. Alphonsus Liguori Theologia Moralis, book II (in the Gaude edition it is a different number, but I forget which) On Sin, chapter 3, on the Capital Sins, Article II, what is Drunkenness? no. 75,

12. Saying the Name of Jesus in Vain. 

In the Second Part of the Second Part, question 122 article 3, St. Thomas Aquinas expounds on Exodus 20:7, “Thou shalt not take the name of…thy God in vain,” by saying that this is actually blasphemy, and that “blasphemy or any word or deed that is an insult to God is much more grievous than perjury.” Thus, saying “Jesus Christ!” in vain (not in prayer or praise or supplication) is a mortal sin. Remember, as I said above, that sins exacting death in the Old Testament usually cause spiritual death in the New Testament. Please remember that the name of Jesus is as holy as the name Yahweh, because it is the same person, God. If someone said the latter in the Old Testament, they would be stoned to death. Nowadays, in the New Covenant, judgment is reserved, which is why we do not die immediately upon committing a mortal sin like saying God’s name in vain.  In short, we have time to confess this sin before judgment. Now, I doubt that saying “Oh my God! is a mortal sin.” Also, if you slam your finger in your car door and yell Our Lord’s Most Holy Name, it is probably not a mortal sin since you did not act with full consent. Obviously, if you’re going through childbirth or being tortured for Christ, yelling the holy name of “Jesus!” is not only not sinful, but even meritorious, as you are begging Him for help!  But just going around and misusing the Holy Name of Jesus in a willy-nilly manner is most certainly a mortal sin that calls down punishment on you and those around you. As I always tell youth groups: “When you say the name of Jesus in prayer, angels come to you and demons flee. When you misuse the name of Jesus, angels flee and demons come to you.”

13. Denying the Catholic faith, including any involvement in the occult, even tarot cards or Ouija boards. 

Jesus said: “So everyone who acknowledges me before men, I also will acknowledge before my Father who is in heaven, but whoever denies me before men, I also will deny before my Father who is in heaven.”—Mt 10:32-33. Dabbling in other religions is a direct denial of Jesus Christ, as is permitting your children to play with tarot cards and Ouija boards. All of these are mortal sins that must be confessed before receiving Holy Communion. Is reading Harry Potter or letting your children read Harry Potter a mortal sin? I don’t know, but I’d encourage you to listen to Fr. Ripperger (an exorcist) at minute 57 here.

14. Skipping Friday Penance. 

From the earliest days of Christianity, Fridays were a day of fasting, since Jesus died for us on a Friday. In fact, all the way up to Vatican II, Catholics had to refrain from meat for about 50 Fridays a year. This was bound under mortal sin. Has that changed? No. The new Code of Canon Law released under Pope John Paul II has only changed the type of penance, not the requirement for a Friday penance. Now, the suggestion is still to stay meatless, but a substitutionary penance is permitted in the new 1983 code. In other words, we are still bound under grave matter to do some penance (physically hard act of returning to God) on Fridays, even if it is not refraining from meat. But to refrain from meat is the clearest indication we are not skirting around such grave matter, so I highly suggest all readers (except the very old, very young, sick and pregnant) to refrain from meat on all Fridays except 1st class Feasts (solemnities in the new calendar.)

15. Receiving Holy Communion with any of the above sins on your heart. 

The Catechism of Pope St. Pius X says: “He who goes to Communion in mortal sin receives Jesus Christ but not His grace; moreover, he commits a sacrilege and renders himself deserving of sentence of damnation.” Furthermore, the Council of Trent (an infallible Council) says: “For no crime is there heavier punishment to be feared from God than for the unholy or irreligious use of the Eucharist.” (Trent, De Euch v.i.) Please, if you have committed any of the above sins, go to confession before receiving the most holy Body and Blood of the Lord.

Finally, if your parish priest or confessor doubts any of the above are mortal sins, please tell him Fr. Dave Nix will debate him publicly on the Magisterium in any place, in any forum (his parish, street corner, or on YouTube) at any time he wants.

 Footnotes:

1.  “Sometimes we are caught off guard by certain symptoms of pleasure immediately following a temptation. At most, this can only be a very slight venial sin. However, it becomes greater if, after we perceived the evil that has befallen us, we carelessly delay for some time and dally with the pleasure to decide whether we ought to allow or reject it. The sin becomes still greater, if, after becoming aware of the pleasure, we dwell on it for some time through downright negligence and without any determination to reject it. When we voluntarily and with full deliberation resolve to take pleasure in such delights, this deliberate purpose is of itself a grave sin if the object in which we take delight is also very evil.”—St. Francis De Sales in “Introduction to the Devout Life,” Chapter 4 part 6 on “How temptation and pleasure may become sinful.”

By Father David Nix|August 3rd, 2019|Theology