Saints LightWhat Is Sin? Mortal and Venial
Sin is a failure of love. A sin is mortal only when it is seriously wrong, we know it, and we freely choose it; otherwise it is venial. God's mercy in Confession is always ready for both.
What this lesson teaches
- Sin is a failure of love toward God and neighbor, not just a broken rule.
- Mortal sin requires grave matter, full knowledge and deliberate consent, all three together.
- Fear, habit and other factors can lessen responsibility, but basic moral law is known to all.
- Mortal sin should be confessed before Communion; venial sin weakens charity and is also good to confess.
Catechism paragraphs this lesson cites
- CCC 1849-1851
- CCC 1854-1861
- CCC 1862-1864
- CCC 1735
- CCC 1458
CCC means the Catechism of the Catholic Church. Saints Light teaches it in its own words and never quotes it. Look up any paragraph in a printed copy or at vatican.va. See every lesson by paragraph in the Catechism index.
Scripture read in this lesson: 1 John 5:16-17; 1 John 1:8-9; Romans 6:23.
A sample question from this lesson
Which three conditions must all be present for a sin to be mortal?
- Grave matter, full knowledge and deliberate consent
- Grave matter, a witness and a broken law
- Bad intention, harm to others and repetition
- Public scandal, full knowledge and anger
Show the answer
Grave matter, full knowledge and deliberate consent. Mortal sin requires grave matter, committed with full knowledge and deliberate consent (CCC 1857).
The lesson in the app has three questions, each with an explanation.
Words to know
- Mortal sin
- A sin of grave matter, committed with full knowledge and deliberate consent, which destroys charity in the soul.
- Venial sin
- A lesser sin that weakens but does not destroy charity.
More terms in the Catholic glossary. More passages in the Scripture index.
Read the full lesson in the app
"What Is Sin? Mortal and Venial" is lesson 6 of Grace, Virtue and Sin. In Saints Light you get the whole teaching, the Scripture quoted in full, all three questions and a step to live it this week.
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Related lessons
- Living as a Christian: Love, Commandments and Virtue (Start Here, free)
- How Do I Make My First Confession? (Becoming Catholic, free)