Expulsion of Adam and Eve, John Faed (1880)

Sin is any thought, word or action that is against God’s law that comes from our hearts. When we disobey God, offend God, or do the opposite of what we know is right, we are sinning.1

Sin’s Effect on Us and Society

Sin turns our hearts away from God and His love for us. It is a disease that hurts our nature and our union as a family.1

How does sin hurt our nature? Like a disease, sin spreads within us. The more we sin, the more it leads us to sin. It does this by driving deep into our hearts, clouding our conscience, corrupting our judgments and casting out our virtues, which all leads to us being more inclined to sin in the future.1

How does sin hurt our union as a family? Like a disease, sin spreads to others. The more we sin, the more it leads others to sin. This leads to concupiscence, violence and injustice to take over our societies and the formation of evil situations and institutions that will lead others to sin.1

The Two Types of Sin

There are two types of sins: mortal and venial.

A mortal sin is any sin that is so grave that it destroys charity in our hearts, removes us from the state of grace and turns us away from God. We have committed a mortal sin when the sin is:

  • Grave;
  • Done with full knowledge; and
  • Done with full consent

A venial sin is any sin that hurts charity in our hearts, but does not destroy it, and does not turn us away from God. Any sin that is not mortal is venial.

Mortal Sins

As we mentioned above, mortal sins destroy charity in our heart, removes us from the state of grace, and turns us away from God. If we are not repentant and forgiven by God, when we die, we are excluded from Heaven and its joys, and will suffer in Hell for eternity.

Is eternity in Hell too long a punishment? No, because we can choose to love and we can choose to sin; this freedom has eternal consequences “with no turning back.” To love in this life means we go to Heaven forever. To sin in this life means we go to Hell forever.

As we mentioned above, mortal sins are any sins that are grave, done with full knowledge and done with full consent.

What does “grave matter” mean?

Grave matter is any thought, word or action that is terrible in nature, such as a violation against God, against our neighbor and against the Ten Commandments.

What does “done with full knowledge” mean?

It means we committed the sin knowing that it was grave; there are certain sins that every person should know are grave (eg. murder).

What does “done with full consent” mean?

It means we had the choice to not sin, but we chose to sin anyway. For any sins we purposefully chose to be ignorant of (eg. skipping Sunday Mass), these are also done with full consent.

Mortal sins are normally only resolved through the Sacrament of Reconciliation. The reason is because, by losing charity in our hearts, God has to work in a new way to bring us back home.

Venial Sins

A venial sin is any sin that weakens charity in our hearts and creates a disordered attachment to worldly things. It makes practicing the virtues and doing what is right more difficult. Though it does not break us off from God, grace or Heaven, it does merit temporal punishment.

If we purposefully commit venial sins and are not repentant, it can lead to mortal sins.

Venial sins can be resolved through charity.

The worst sins

Of all the sins we can commit, the following are the worst.

Sins against the Holy Spirit

These are mortal sins where we reject the Holy Spirit and thereby harden our souls. These sins are: despair, presumption, envy, obstinacy in sin, final impenitence and purposeful resistance to the known truth.

(Sin against the Holy Spirit)

Not trusting that God will forgive you of your sins, thinking that your sins are beyond Christ’s redemption.

(Sin against the Holy Spirit)

Thinking that you can commit a sin because God will give you a chance to repent.

(Sin against the Holy Spirit)

Purposefully being distressed by someone else’s good fortune.1

Obstinacy in Sin
(Sin against the Holy Spirit)

Purposely maintaining a sinful habit.

Final Impenitence
(Sin against the Holy Spirit)

Not repenting of your sins, not seeking God’s forgiveness and friendship, and holding onto your mortal sin until death.

Purposeful Resistance to the Known Truth
(Sin against the Holy Spirit)

Knowing that something is true, but behaving as if it was not. For example, knowing that Hell is a real punishment, but living your life as if you’d never go there.

Sins that cry to Heaven

These are sins that call for vengeance. These sins are murder (Genesis 4:10), sodomy (Genesis 19:13) and oppression of the poor, the foreigner, the widow, orphan and wage earner (Exodus 2:23).1, 2

Capital Sins

These are sins that lead to other sins. These are: pride, avarice, envy, wrath, lust, gluttony, sloth and acedia.


Choosing to commit an evil with the desire of harming someone else. These are one of the worst forms of sin.1

Responsibility for Sin

There are certain cases where we may not be responsible for the full gravity of our sin, such as when we act out of passion, or if we suffer from a disorder, or if we just didn’t know.

But, no matter how much of a disease sin is to our soul, it cannot destroy our sense of what is right and wrong. So, though we may not know the gravity of a sin we might commit, we will always be able to tell it is a sin, and therefore we will be responsible for it.

We are also responsible for the sins we cause in others. If we participate in another person’s sin, help them with their sin, encourage them when they sin, do not attempt to stop them when they sin (when we are obligated to) or protect them from justice, we are responsible for causing them to sin.

God’s Mercy

God permits us to sin because:

“God has consigned all men to disobedience, that he may have mercy upon all” – Romans 11:32

And there is no limit to God’s mercy. As such, there is no limit to God’s forgiveness of our sins. You can always seek God’s forgiveness.

But, we can reject His mercy and forgiveness by not repenting. As such, we can also reject salvation. This refusal to repent is called “hardness of heart” and leads to final impenitence and Hell.

We cannot tell if a specific person is lost to Hell. We can judge their acts in life, but only God can judge the person.