Three things are necessary for a sin to be mortal:
As a result of Original Sin, human nature is weakened. Baptism, by imparting the life of Christ's grace, takes away Original Sin, and turns us back toward God. The consequences of this weakness and the inclination to evil persist, and we often commit personal or actual sin.
Actual sin is sin which people commit. There are two kinds of actual sin, mortal and venial.
Mortal sin is a deadly offense against God, so horrible that it destroys the life of grace in the soul. Three simultaneous conditions must be fulfilled for a mortal sin:1. Serious matter (things listed in this examination);
2. Knowledge or firm belief that the act is seriously wrong prior to committing the act;
3. Full consent of the will.
All three of these conditions must be present simultaneously for a sin to be mortal. This means that if you did not know the act was seriously wrong, then you are not guilty of having committed a mortal sin. If you did not will the act, e.g., if you were forced or if it was in a dream, if you were impaired or emotionally distraught or terrified, etc., you are not guilty of the act committed.
All mortal sins committed since your last confession must be confessed by both type and number, i.e., the kind or "name" of the sin and how many times or frequency it was done. If there is a mortal sin from the past that was forgotten and has not been confessed, once remembered it should be confessed at your very next confession.
It is not necessary to confess venial sins, but it is a good and pious practice.
1. I am the Lord your God. You shall not have strange gods before me.
- Involvement in occult practices, e.g., witchcraft, ouija boards, seances, palm reading, tarot cards, hypnotism, divination, astrology, black magic, sorcery, etc.
- Involvement in or adherence to New Age or Eastern philosophies, atheism or agnosticism
- Apostasy (leaving the Church)
- Adherence to a schismatic group
- Putting faith in superstition, e.g., horoscopes, good luck charms, etc.
- Joining the Masons or other secret society
- Receiving Holy Communion in the state of mortal sin
- Receiving the Sacraments of Confirmation or Matrimony while in the state of mortal sin
- Willful participation in illicit (non-emergency) “General Absolution” services
- Being married by a Justice of the Peace or by a minister of another denomination (without dispensation)
- Involvement in false or pagan worship
- Willfully denying the Faith of the Catholic Church
- Despair of God’s grace or mercy
- Presumption (committing a mortal sin with the idea that you can just go to confession)
- Hatred of God
- Simony (buying or selling spiritual things)
- Failure to receive Holy Communion at least once per year ( if possible, during the Easter Season)
- Desecration of the Holy Eucharist
2. You shall not take the name of the Lord your God in vain.
- Using God’s name intentionally as a curse
- Seriously wishing evil upon another
- Serious slander or insult of a sacred person or object
- Making an oath in a secret society
- Telling a lie or withholding a serious sin in confession
- Blasphemy (words of hatred, reproach or defiance toward God; speaking ill of God)
- Perjury (lying under oath)
- Swearing false oaths
3. Remember to keep holy the Lord’s Day.
- Missing Mass on Sunday or a Holy Day of Obligation without a serious reason
- Doing unnecessary work on Sunday for a long period of time, i.e., more than several hours
- Intentional failure to fast or abstain on appointed days
- Requiring employees to work on Sunday in non-essential occupations
4. Honor your father and mother.
- Serious failure to care for aged parents
- Serious neglect of the duties of one’s state in life
- Serious disrespect for or disobedience to parents, superiors or authorities
- Wishing death or evil on parents
- Abuse or serious neglect of children
- Failure to baptize children in a reasonable time (within a few months) after birth
- Serious neglect of the religious education or upbringing of children
- Failure to carry out the last will of deceased parents
- Murder, homicide or manslaughter
- Procurement of an abortion
- Promoting, counseling or paying for an abortion
- Knowingly voting for someone who is pro-abortion
- Willfully injuring or trying to hurt another person
- Willfully leading another into serious sin
- Driving dangerously or recklessly
- Driving under the influence of drugs or alcohol
- Willfully harboring hatred for another
- Taking or selling illegal drugs
- Willful drunkenness
- Self mutilation
- Excessive tattoos
- Excessive body piercing
- Piercing of the nipples or sexual organs
- Sterilization
- Promotion of or involvement in euthanasia
- Serious entertainment of suicidal thoughts
- Attempting or intending suicide
- Willful failure to bury the body or ashes of the dead
- Willful engagement in unjust lawsuits
- Bigotry (hatred for persons of other races)
- Intentionally placing temptation before the weak
6. You shall not commit adultery.
- Adultery
- Fornication (intercourse prior to marriage)
- Masturbation or other impure acts with self
- Homosexual acts
- Using a contraceptive
- Dressing or acting in a manner intended to cause arousal in another (spouses excepted)
- Kissing or touching another passionately for the purpose of arousal (spouses excepted)
- Allowing another to kiss or touch you in a sexual manner (spouses excepted)
- Intentionally causing a sexual climax outside of intercourse
- Onanism, i.e. intentional withdrawal and non-vaginal ejaculation
- Flagrant immodesty in dress
- Bestiality (sexual acts with animals)
- Oral, anal or other degrading sex practices
- Prostitution
- Rape
- In-vitro fertilization or artificial insemination
- Surrogate motherhood
- “Selective reduction” of babies in the womb
- Types of fertility testing that involve immoral acts
- Involvement in or support of human cloning
- Willful divorce or desertion
- Incest
- Polygamy or polyandry (many wives/husbands)
- Cohabitation prior to marriage
- Destroying the innocence of another by seducing or introducing them to immorality
- Lust in the heart (“if I could I would”)
- “Swinging” or wife swapping
- Cross-dressing
- Stealing a large amount of money or a valuable item
- Willfully destroying or defacing another’s property
- Stealing something consecrated to God or from a holy place
- Buying, selling, receiving or concealing items known to be stolen
- Willful failure to make restitution
- Excessive gambling
- Defrauding workers of their wages
- Serious failure to fulfill work requirements
- Padding expense or per diem accounts
- Taking advantage of the poor, simple, inexperienced or less fortunate
- Denying help to the poor, needy or destitute when able to help them easily
- Defrauding creditors
- Bribery or taking bribes
- Blackmail
- Fraud or embezzlement
- Price fixing
- Tax evasion
- Forgery
- Excessive waste or expense
- Slavery
- Serious cruelty to animals
- Violating copyrights and illegal copying of software
8. You shall not bear false witness against your neighbor.
- False witness (not under oath) or perjury (under oath)
-Telling large or premeditated lies
- Serious gossip, detraction (revealing the faults of another without serious reason), or calumny (harming the reputation of another by falsities)
- Violation of a confidence without good reason
- Being an accomplice to another’s grave sin
9. You shall not desire your neighbor’s wife.
- Viewing pornography in books, magazines, movies, the internet, etc.
- Reading sexually explicit materials
- Dwelling on impure thoughts or fantasies for the purpose of arousal
- Willfully lusting after another
10. You shall not desire your neighbor’s goods.
- Serious and willful greed or avarice
- Intention to steal or destroy the goods of another