Sin an act

Sin I have always been told must be an act. Jesus said if you look at a woman and lust in your heart Now what does that mean? Is lust an act? “In your heart” is that a thought? Is it a feeling?


Sin must always be an act of the will.

We can of course sin in our thoughts, as we admit each Sunday at Holy Mass.

As a dear priest says, “I’m a mass murder—but, by God’s grace, I haven’t ended anyone’s life.”

Forgive me for being blunt, but we can “murder” people in our heart, due to anger, just as much as we can “rape” them in our heart with lust.

But the will has to be involved, and many passing thoughts in our mind haven’t been directly willed.

OK what about a situation of lust. Some larger women can well, have some trouble with the average wardrobe. I realize this is a person. But if a woman is showing too much it’s hard not to notice, being a guy. It seems to me to be very easy in that situation to fall into sin.


Is the will an act? Or a power? I believe Aquinas calls the will a “power”. As in will power. There is a difference in a power and an act. Perhaps the will can be both. Again IDK. My issues seem to be right up front and center above others sexual things. I am tired of sinning. I want to stop. So I need to understand what is right and wrong, and how to defeat things. I know we can’t do it on our own.

Will is cooperation or wanting. However, sexual desire is not sinful unless it is dwelt or acted upon in an immoral/perverted way. Thinking about unitive love with the opposite sex is not necessarily a sin. It depends on what the intentions of your thoughts are. Do you desire a spouse or a moments pleasure.

Here’s what I was taught:

Do you see someone and have a lustful (or angry, or whatever) thought? You didn’t call it; it is not an act of the will–that is, it is not a result of a decision you have made. No sin.

OK, so that is the first instant. After that, do you push the thought away, or do you hang on to it? In your head is it, “Argh, another lustful thought–no!” Or is it “Another lustful thought, hmm, well it’s already here, so it can’t much matter if I keep on with it…” You can see the difference. The first is no sin, the second is.

Now you still want to fight the having of that first instant of lustful thought, because it can lead you into sin, not because it is sinful itself. I didn’t need it so much with lust, but with anger, I basically tried to shorten the length of the instant, replacing it not with anger and frustration at myself, but with gratitude for all God has done for me–all of the sins he Has forgiven. It helped me. I’m not sure if it would work the same way with lust, but you could give it a try.


Seeing a woman, and being tempted by her, is not a sin.

Sin enters the equation when one actively wills and consents to something illicit, in this case, illicit sexual intercourse.

Distinguishing mere thoughts and temptations from acts of the will is something that can be problematic for those who are scrupulous, especially when there are grey areas concerned.

Also difficult might be distinguishing consent from non-consent, and scrupulous people can wrap themselves into all kinds of knots trying to figure this out.

… and in line with my comment about scrupulosity, it is best to consult with a priest about whether or not he sees you as possibly suffering from scruples.

In the meantime, this article might give you some principles you can use:

Nothing wrong with appreciating the appearance of another person, it becomes sinful when you begin creating fantasy scenarios about sexual situations involving them and yourself. That’s your act - doesn’t have to be physical. IMHO.

If just seeing a good looking person jumps your mind to sexual thoughts, well, you probably need more help than a bunch of anonymous posters on here can provide!

I give the example of say a woman bends over and things show. I happen to see this in the corner of my eye. I look and as you say, “appreciate”, do a double take. :shrug: That sounds wrong.

You weren’t looking for a look, so to speak, it was an accident, you saw it and went on with your life, case closed! No whistle, you didn’t embarass her or make a scene…

Of course I’m 60, happily married, and don’t get too upset about most anything!

If you are really bothered, just cross yourself, say excuse me, and leave!

No I don’t like to make gross comments. And I don’t want to embarrass anyone. I wouldn’t be bothered by it.

I wrote this on another forum to someone struggling with lust, or feelings they were afraid would become lust and where the line is drawn between sinfulness and non-sinfulness. Maybe something in here will be applicable to your current questions.

“Here’s the thing. Just because you have that passion doesn’t mean you automatically are in sin. The devil has a certain dominion over our flesh because of original sin. Those passions are there to enable attraction to a female but the devil often tries to take advantage of those passions. Jesus is truth so you must be like Jesus and be truthful. If you are having a strong passionate feeling like that, simply tell God you being tempted and you feel like you want to commit that sin and ask him to subdue those unruly passions for you. Also ask help from Mary. It is not a sin just because the devil is using your feelings and passions against you and you are being pulled in that way in hopes for you to ACTUALLY COMMIT a sin. Now if you keep dwelling on it and then resisting and then dwelling on the temptation and then resisting and then dwell on the temptation again and resist again. Then that’s where you can run into some sinful behavior. Because you are purposefully bringing your mind back to the sin because you want yourself to be overcome with passion in order to commit the sin. It’s almost as if one wants to be so weak and so over run that they cannot resist it anymore. But why would somebody do that subconsciously? Because subconsciously they may feel they will be less guilty if they commit the sin since they were so overcome with temptation. Almost as if someone wants to induce impulsivity. What we are supposed to do is when you have those temptations immediately thwart them and train your mind to move on to something else. How do you thwart them when you are feeling extremely weak? Again just simply pray to God with honesty and don’t keep dwelling on it.”

Yes. Retraining the mind is a job. And I would think that could be scary. It’s not the habit. Creating something new feels odd. I have experienced that.

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