How to be really sure it's mortal?


Brothers and Sisters,

As I’ve mentioned in some previous threads, I am currently engaged on a struggle for purity. The situation has certainly been improving, but sometimes I keep falling in the masturbation sin.

It usually happens in the morning (I shall take measures against this), where I’m usually not very well awaken. I’m been to the confession a lot, and the priests to who I talk to (who happen to be quite ortodox) are divided. Some warn me to not to focus too much on that issue, and to avoid being scrupulous, others don’t make any comment about my behaviour.

I am wondering: how can you be really sure of the nature of your sin? I certainly have to ask this to my spiritual director, but I’ll only meet him in 3 weeks or so.

Probably some of you will say: “Well, it will appear obvious to you if you pray and if you meditate about it”. Yes, sometimes it’s obvious, but in cases where the border isn’t clear, if I meditate and reach the conclusion that it was not a mortal sin, how can I know that I’m not being fooled by the devil?



Well, for a sin to be mortal, one must be willfully consenting to committing it, and one must have the full knowledge that it’s sinful. If you are seeking to derive sexual pleasure from doing so, and you are thinking to yourself, I know this to be wrong, but do it anyways–then it most likely is a mortal sin. I hesitate to judge, because I am not in your mind or your heart–so only you and God know for sure. But, when in doubt, I always confess those sins that seem ‘grey’ to me. You can’t go wrong by confessing them. I will keep you in my prayers.

Blessings to you,


For a sin to be mortal, these three factors need to be met

*]its subject must be a grave (or serious) matter;
*]it must be committed with full knowledge, both of the sin and of the gravity of the offense;
*]it must be committed with deliberate and complete consent.[/LIST]



The Catechism of the Catholic Church (sometimes abreviated CCC with a paragraph #) gives accurate, official teachings about many issues that might come up in your life as a Catholic. There is a topic index.

Masturbation is discussed in paragraph 2352. The catechism makes it clear that it is a serious sin. You can read the catechism in an online version. I don’t have the link saved on this computer, but you can easily find it with a search engine.

If you didn’t know that it was a serious sin when you engaged in it previously, then the sin was not mortal. However, you might want to confess it anyway if it was a repeated problem. Mortal sin separates us from God and injures our relationship with Him This is why mortal sins must be confessed in order to repair our relationship with Him before receiving communion. Repeating the same venial sins still harm us because they can lead us down the slippery slope and into mortal sin. I can tell you this is true from my own life.

Now, you do know that masturbation is a serious sin in the teachings of the church. Perhaps this will make it easier to resist the temptation since you know that it injures your relationship with God. Christ gave His very life for you, so I’m sure that you will find a way to resist injuring Him for a few minutes of pleasure. You may need to find some help by reading a book on how to change your habits or getting counsel from your priest, etc. I suggest placing a crucifix or other religious item in your bedroom (or anywhere needed) where it might be a visible reminder not to sin.


Or you can wear one that you can touch (and you probably already do). It doesn’t have to be visible. You will know where it is. Many people have done that. It has helped me too.


Others have already given you the three requirements for a sin to be mortal. My view is if it involves objectively grave matter, confess it. It is true that you may not have committed a mortal sin since you might not be subjectively culpable, but doesn’t it make sense to err on the side of caution and confess serious sin? Besides, the sacrament of confession provides healing and graces to help you avoid future sin.


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