Skip or receive communion when not sure whether a sin is mortal?


I realized I have trouble knowing if some sins are mortal or venial, even though I’ve heard the criteria so many times. Sometimes I’m in mass and I suddenly remember a sin I committed recently and I’m torn between whether it’s mortal or not. Is it better to refrain from communion just in case? Or is it OK to receive because if the sin really were mortal, I would probably know it?

Thanks in advance.


In the situation you laid out, it sounds like you should receive. Take advantage of reconciliation frequently.

Most importantly, talk to an intelligent priest about this.


Do you have any sort of tendency toward scrupulous thinking?


Go ahead and receive. Go to confession too. It’s all good.


If you’re having a lot of trouble with this, speaking to a priest is best. Let him guide you and follow his advice.


The criteria is to confess any grave sins we know to have on our souls before receiving the Eucharist. The Catechism can give some good guidance on which sins are grave. The other two criteria for mortal guilt are full knowledge, and full consent of the will and not knowing you I cannot say whether or not you meet these subjective criteria. However the gravity of a sin is an objective criterion and it is an excellent idea to confess them. If it turns out that your confessor says your culpability is not mortal because of extenuating factors (habit, addiction, etc. can mess with our ability to give full consent to gravely sinful acts) and he says it is not necessary to confess this sin each time it happens, then follow his advice. He is trying to help you avoid falling into scrupulosity which then leads to hopelessness and loss of faith, a favourite trick of the wily one.

It sounds like, in addition to a regular confessor, you’d benefit from a spiritual director.


I hope that I’m not being over simplistic, but if one has no idea as to whether a sin is mortal or venial, then surely full knowledge cannot be present.


A sin can not be mortal without full knowledge. So there is really no risk in this case


When in doubt, sit it out.

Unless you are scrupulous, then, abide by what your Confessor says.

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