Is it a sin to not tell someone they're committing grave matter(possibly mortal) sins?

Ok so I’m a college student home for the summer. I went out to eat with a friend from home that I haven’t seen in a while, she and her family are Catholic but she casually shared with me that she missed Mass today(she doesn’t drive and apparently she slept in or her dad couldn’t take her or something, even though our Parish has a 7pm mass but I don’t know) so I immediately said she could have gone to the 7pm mass, but I didn’t push it further than that. So the rest of the time I’m sitting there while she’s talking about whatever thinking to myself if I should be warning her about mortal sin and what my obligation was at that point, I’m very scrupulous so this really was agonizing to me. I thought that maybe I could type her a message about it since I’m not good at talking about serious things like that. The later she’s telling me how her and her college friends drink and how she wants to get drunk when she gets back to school and honestly I didn’t say anything about that and she just moved on to the next topic of conversation. All I can say is I’m obviously worried for her but I’m also super scrupulous about myself and don’t know if I should go to confession tomorrow or not?

You are obviously a young person who holds the truths of their faith very close to their heart. She may eventually not be the sort of friend you will find conducive to a solid catholic life style, however she is unfortunately an example of the vacuous unthinking youth of her age, ignoring her faith at the risk of losing her values if not her soul.
However, if you admonish everyone of your friends for all their faults you will have no one around you very quickly. If she has respect for you you can mention how seriously you feel about Sunday Mass attendance, even offering to take her when she misses in the morning.
However, I doubt that you are specifically sinning by not taking the mite out of everyone’s eye, but rather place greater importance in your own spiritual growth without becoming scrupulous. Lead by example and let your light shine.

It would be good to go to confession if you wish to, I think.

Practically, yes, I think it would be good to tell her that not going to mass is a serious sin.

Definitely pray for her no matter what, that is a great act of charity that will be helpful to her and God will be pleased with.

I think there are times when perhaps we should refrain from speaking if the person is not going to receive it well, but I’m not really certain on this point.

I think one should pray at these times right before they speak and try to discern in their heart if and what they might say.

If you are scrupulous, obligations are not binding for you.

Also, you need to find one spiritual director for these kinds of questions. :thumbsup:

I think it is always good to look for ways to practice the Spiritual Works of Mercy:

Admonish the sinner
Instruct the ignorant (This and the next work are extremely pertinent categories today, when so many people are confused by what the Church teaches on contraception, abortion, homosexuality, etc.)
Counsel the doubtful
Comfort the sorrowful
Bear wrongs patiently
Forgive all injuries
Pray for the living and the dead

9 Ways To Be an Accessory to Sin

The question was:

Is it a sin to not tell someone they’re committing grave matter (possibly mortal) sins?

9 Ways To Be an Accessory to Sin

  1. By Silence (peccatum taciturnitatis or the sin of silence)
  2. By Counsel
  3. By Command
  4. By Concealment
  5. By Consent
  6. By Partaking
  7. By Provocation
  8. By Praise (or Flattery)
  9. By Defense of the Ill Done

Hopefully this helps answer your question.

God bless.


Very good topic. Believe me, if I were to admonish all my non practicing catholic family members and friends I would be considered a pariah. Most of them are so anti Church I am always met with hostility or indifference if I bring up a sin or church teaching.

But you really have to treat each individual differently. Some may be more receptive to what you want to say.

Since you are scrupulous, if you don’t already, get a regular confessor that you can ask these sort of questions so that he can give you proper guidance through your scruples. This is very helpful if you haven’t already done so. :slight_smile:

It is commendable to try and tell people that what they are doing is a grave sin, but sometimes it is not necessary. If someone would not change what they are doing even if you told them it is a mortal sin, then you need not inform them of it.

yes find a spiritual director

and also, that’s life when your a Catholic you’ll come across these situations all the time.

A lot of my family don’t talk to me because I’m generally up front about it and I’ve lost a friend or two but who knows, they may appreciate it one day.

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