Catholics who are not religious

Is it a sin for Catholics who don’t go to church barely, or not know what mortal and venial sins are, etc. ? Because, I know a Catholic girl who claims she knows the difference but thinks the only mortal sin is killing someone. When I told her sex, and other things are also mortal she laughed and thought I was weird. My question would be, that do Catholics have an obligation to find out these things for themselves ? And is it a sin if they don’t and go along w the way they are -not going to church, getting drunk, and other bad rhings ?

It’s a little too long to write, so please see the CCC, Second Edition.
“Erroneous Judgement” 1791 & 1792,
Yes, ignorance “can” be a sin, and the person “can” be culpable for the evil he commits in ignorance.
The Catechism explains the circumstances.

Actually, killing someone is not nessecarily a mortal sin, (see catechism 1859)

Section 1858 explains what a grave offence is:

**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.” 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.

Section 1859 explains consent further;

**1859 **Mortal sin requires full knowledge and complete consent. It presupposes knowledge of the sinful character of the act, of its opposition to God’s law. It also implies a consent sufficiently deliberate to be a personal choice. Feigned ignorance and hardness of heart do not diminish, but rather increase, the voluntary character of a sin.
Section 1860 of the catechism reads thus;

**1860 **Unintentional ignorance can diminish or even remove the imputability of a grave offense. But no one is deemed to be ignorant of the principles of the moral law, which are written in the conscience of every man. The promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders. Sin committed through malice, by deliberate choice of evil, is the gravest.

I would suggest you advise her to speak to a Priest, or get her a copy of the Catechism if she feels she understands Catholocism.


You’ve asked a lot in a little space.

Yes Catholics have the obligation to learn what the church teaches and to abide by those teachings.

That being said, there are a lot of different levels and factors that can, and probably are, at work here.

Is this person truly ignorant, or does she think she knows because of bad information that she has received from other catholics, or possibly even teachers or clergy.

Then there is the question of whether this person is truly serious about her faith or if it is just a “cultural” thing because whe was “born catholic”. There are many around who are like that.

Overall it is obvious that your friend has not been properly taught (catechized) and I am sure that you can help her gently to learn more about the faith directly from the Catechism.


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