How do we know if is sin is grave?

All of the lists of grave sins I’ve seen are based on the ten commandments, and expanded upon them. How do we know that the sins listed are grave? For example, under Thou Shalt Not Murder, it will talk about being angry with someone. Or under Thou Shalt Not Commit Adultery, it will list looking with lust. Are we to assume these are grave sins?

**1. Are all grave sins related to the ten commandments?

  1. Is there some standard or rule by which we may judge whether a sin is serious?

  2. If you’re not scrupulous, can you rely on your conscience to alert you to many or most grave sins? (I know the conscience is not totally reliable because there are some sins I know are serious that my conscience would not feel bad about.)**

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.

The obligation of the Decalogue

2072 Since they express man’s fundamental duties towards God and towards his neighbor, the Ten Commandments reveal, in their primordial content, grave obligations. They are fundamentally immutable, and they oblige always and everywhere. No one can dispense from them. The Ten Commandments are engraved by God in the human heart.

2073 Obedience to the Commandments also implies obligations in matter which is, in itself, light. Thus abusive language is forbidden by the fifth commandment, but would be a grave offense only as a result of circumstances or the offender’s intention.

Scripture, the Teachings of the Church such as see in the CCC, Orthodox Catholic Moral Theology works…etc

One must form ones conscience with such truth…

While feelings may enter into things (and often they can and such can “perfect” things conscience is not per se about feelings. Rather reason…

And of course as Christians -Faith is very much involved. Following Christ…walking in the Spirit…

That is the best explanation I have ever seen. Thank you.

Thank Pope Saint John Paul II, then Cardinal Ratzinger et al…


Many sins are mentioned in the Letters of the New Testament including homosexuality, fornication, sorcery etc.

Once again, Bookcat comes to the rescue :smiley:

Try this. It gives you a good list.

I do not recommend that list per se (it is the authors compiled list of examples and though much is on target - some things need more explanation etc).

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