Question regarding mortal sin


I’m going to keep this short, my question is what happens if someone commits a mortal sin without thinking. What I mean is they know that the act is a big sin but do it without thinking and are NOT like “Oh this is a huge offense against God, yeah it’s evil and it’s sin but i’m going to do it anyway” Would this still count as mortal sin? One of the three things for a mortal sin must be Full Knowledge, meaning that you must know what you are about to do is evil and against God but yet it’s not like you do have knowledge since you weren’t thinking. I’m really confused, should I go to confession?


Can’t have a mortal sin without thinking.


I think you might be referring to swearing on reflex. Reflexes are inherently subconscious, so you can’t consent to something like that. However, if i’m not right, I’d need to know what you are referring to so I can answer.


Uh I don’t even know what that is. What I was trying to say is in the original post was would mortal sin count as mortal sin even if the person knew that mortal sin was a huge offense towards God but wasn’t thinking about that when they did it.


Serious matter

Know it is a sin

Do it on purpose

Those three things must happen for the sin to be mortal.


If they thought about it, even for a brief second, the sin would be mortal. Also, if they intuitively “knew” the sin was wrong, while not actually thinking it, the sin would still be mortal. The way it could not be mortal is if before they committed the action, they saw nothing wrong with doing it.


If the sin was a knee-jerk reaction, without any though, it would likely be venial. However, if there was any premeditation, the sin is mortal.


Flip Wilson, a comic decades ago, was famous for his line “The DEVIL made me do it”. This framed the way we want to push blame for our sins onto anyone else. Heck, Adam blamed Eve, Eve blamed the snake.

We sin in “what I have done and what I fail to do”.

If you are holding a gun and you have some sort of seizure or muscle spasm that pulls the trigger, one did it “without thinking about it”.

When we sin, whether we want to admit it to ourselves, we are thinking about it. Perhaps we have become so spiritually numb that we simply allow our passions to rule and, in that way, we don’t think about it. The sin has become so frequent it is now a habit.

I have a habit, I absentmindedly will pinch at little hairs on my chin. I’ve done this for decades. It is impolite and crude and I should not do it in front of people, but, I have done it for so long that I no longer think about it. Thing is, the first times when I did it, it was deliberate. I then allowed it to grow into a habit. I am working on breaking this habit.

So, if you have a sin in your life that has grown into a habit, it is time to break the habit. Scripture tells us that we are to control the things we say, we are to have mastery over our bodies, St Paul often compares the Christian life to an athlete training and competing.

Start thinking about whatever has become a habitual sin.

This is a very good book:


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