Is it possible to commit a mortal sin if you don't know that mortal sin exists?


I grew up evangelical. I have a valid baptism. I was always taught that you could not lose your salvation, and that all sin is equal in God’s eyes. I committed some grave sins in my youth, but I did not realize that they would separate me from God. I knew they were sins, and also that they were serious sins (even though I was taught that all sins were equal in a God’s eyes, at some level I realized this was not true). I did not know or realize that these sins would take me out of a state of grace though. I probably would’ve made better choice had I realized that.

So, are sins committed in these circumstances mortal? Now that I am joining the church, must I confess these serious sins at my first reconciliation even though I didn’t realize that they would severe my relationship with God at the time?

There were also a few sins that the Catholic Church teaches are grave, but that I was taught weren’t sins. Are those mortal sins when I didn’t realize they were sins at all?

Yes, it is possible to be guilty of a mortal sin even if we do not understand the specific concept of a mortal sin. Through our reason and conscience we can certainly know that something is gravely wrong. This, at its most basic level, is what we refer to as the natural law.

Obviously, because we suffer from Original Sin our understanding of what is gravely wrong can be distorted. In such situations, if the distortion is through no fault of our own it can indeed lessen our culpability.

In general, if someone was aware that something was gravely wrong and freely chose to do it anyways they should confess it even if they had committed it at a time when they didn’t understand the specific concept of mortal sin.

As for grave sins that someone didn’t truly understand to be wrong at the time they were committed, that is best discussed with a spiritual director but they could also just be confessed “to be safe.”

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