How do I know if a sin is mortal?


I have spoken to my priest, confessor and spiritual director (PCSD) about similar matters. I also have these unbearable, sometimes foolish. my PCSD stated at these quick fleeting moments of uncertainty and anxiety, to just invite Christ into your mind at that point, sharing with him your thoughts, so that he may give you peace of mind and the anxiety should cease. there are many things you can do to help over time, so that when you have theses thoughts again, you can offer them to Christ. I am sorry if this doesn't help. I would also suggest talking to your PCSD about the matter so that your mind and soul may be at peace. God Bless.


Thanks so much for the advice! It’s all so helpful! :slight_smile:


Taken from a very reputable book from the 19th century called *The Way of Interior Peace *by Fr. Eduard Lehen, pg. 99:

"To a mortal sin belong three points: 1st. Weighty matter; -- a jesting lie, for example or a vain, self-conceited thought, is not sufficient for a mortal sin. 2d. Full knowledge of the evil; that is, the deliberate consciousness that what one does is a mortal sin. This excludes all cases in which the sin proceeds from surprise, or in which the soul is not full master of her powers; as, for example, in half-slumber, and the like. 3d. Full consent of the will to that which the understanding knows to be mortal sin. As long as the consent remains imperfect, or we are conscious of a certain hesitancy, a deferring, or a reproach of conscience in consequence of our neglect in combating the temptation, the sin is only venial."

I hope this helps.


[quote="Nickname_Sam, post:1, topic:328463"]
I thought about something and someone that I thought would maybe get me sexually aroused, and sure enough, it happened. I dwelt on the feeling for a few seconds when I noticed it was happening, but felt extremely guilty right after. The whole thing happened in about five seconds, so I don't even know if I gave full consent or not or if I knew for sure it was mortal and did it anyway. I know if I had asked myself, "Do I want to commit a mortal sin?" the answer would have been no, but how do I decide if it was mortal or not when it was so fast? Also, does it make it worse that it was someone of my same sex I was thinking about?


A good rule of thumb given to me by a very solid priest:

No intention + no consent of the will (you squelch the thought, avert your eyes immediately, etc.) = no sin.

No intention + some consent of the will (your eyes linger for a moment, your thoughts dwell for a few seconds, etc.) = venial sin.

No intention + full consent of the will (you "own" the act and embroil yourself in lust, entertaining the thoughts, oggling the body, etc.) = mortal sin.

Intention = mortal sin.


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