Is not warning another about grave sin a mortal sin?


Ok so I’m a bit scrupulous but I need to know if I committed a mortal sin or not.

Today my mother and I were getting ready for 8am mass, our Priest is usually done with daily Mass around 8:30 so I don’t eat after 7:15. It was 8:27 and my Mom was drinking tea or coffee so I reminded her of the communion fast and then I left.

Before leaving the house I googled it and found out that breaking the fast is grave matter. My mother had already left (we were taking separate cars) so I wondered what I should do. Should I call her and tell her not to receive? Should I tell her in the pew before mass? I decided that since I was so unsure of my obligations at this point I wouldn’t do anything until after mass, both of us received communion.

After mass I told her that it is grave matter and she just said ok and sounded somewhat surprised. But now I’m worried that I was an “accessory to grave sin” since I knew she was going to receive communion after possibly breaking the fast and didn’t try to stop her and I’m really worried that I’ve committed two mortal sins, one for not warning her and one for receiving communion.



I would encourage you to talk to a priest about scrupulosity.


You reminded her of the fast. That’s all you needed to do. Whether she acts on that or not is not your fault. Being an accessory to sin actually refers to active participation in one’s sin, not the attempt to head off potential sin. After all, breaking the communion fast is only a sin if someone breaks the fast and then receives. It is not necessary to fast simply because one is going to Mass–only if one intends to receive.

If you are scrupulous, you need to consult with a trusted confessor or spiritual director, and not the potentially diverse and contradictory opinions on the internet, which will only serve to further disturb and disquiet your conscience. You are in my prayers.



I understand your worries. You want so badly to please the Lord, not to err in any way and be separated from Him or His love.

These little nagging doubts are NOT what Christ Jesus had in mind for you when He called you out to be His child.

Turn your face towards His, and away from these pinpricks of conscience that come from you-know-where and are designed to distract us from the joy of God’s presence in your day.

Go out and rejoice in your place in God’s plan. Look at the bigger picture He has in mind for you, and let the little demons slink off in the light of day.


I don’t know about you, but most Catholics take sin serious. It is a serious sin to not fast at least an hour before receiving. The poster has a legitimate concern and needs a proper answer not cute little whimsical platitudes.


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