Are all sexual sins mortal and does thinking of sex without the need for arousal a mortal sin?
When does the thought become mortal; is it when we don’t control it or is it always mortal?

what exactly is lust and what are the church’s teaching on it? Is it always mortal as well?

From my understanding, something has to be grave matter to be mortal and anything sexual is grave matter.
So if you are doing something sexual and it is a sin, then it is by its nature a mortal sin.
But there are all kinds of variables which include things like psychology that might reduce your culpability and you might not be culpable of mortal sin.
I know actions that are sexual sins are by their nature mortal, but I am not sure about thoughts.

If you want the thoughts are wanted and keeped arounf maybe mortal, if not wanted then maybe not.:):tiphat::gopray2:

Impure thoughts which pop into your head are not in themselves sinful but dwelling on them for sexual pleasure is a sin a grave matter.

All sexual acts outside marriage are sins of grave matter.

Lust is always a sin of grave matter.

2351 Lust is disordered desire for or inordinate enjoyment of sexual pleasure. Sexual pleasure is morally disordered when sought for itself, isolated from its procreative and unitive purposes.

Lust is a mortal sin if you dwell on it and realize you are lusting and decide to continue lusting anyways. I don’t think it’s a mortal sin if you realize you are lusting and then stop immediately.

Lust is not an impure thought. Lust is an impure thought that is dwelled upon for sexual pleasure. Lust is always a sin of grave matter.
An impure thought that pops into your head and you dismiss immediately is not.

Sex itself is not sinful-- it is a gift from God given for us to use in marriage–using it outside this intended purpose is mortal sin. Looking at a naked body in and of itself is not sinful either. The sin comes from within you–from lusting. From using that person for your own self-gratification whether in your thoughts, words, or actions. That is the point you stop treating that person with the dignity they deserve as child of God–as your brother or sister in Christ and begin treating them as an object for your gratification (this is the mortal sin).

In this day and age we need to guard ourselves from the near occasion of sin of lust, especially those who are weak against the temptation (FYI, I was one of those people at one time so I have a bit of experience). Marketing people target us with the temptation of lust to get us to buy their products.

Compare a billboard today with something like a painting of Michaelangelo. In Michaelangelo’s work it is simply a naked person, painted as to be realistic and beautiful in a non-sexual way. Where many advertisements today they have more clothes but are made to draw your eyes to the breast or groin to get you to lust. Because of this you may find your eyes caught for a few seconds by a billboard, but once you realize it is happening you must stop to avoid sin.

It is not good to tempt with sin. All sin saddens God, regardless of whether or not it is mortal. St. Francis De Sales in “Introduction to the Devout Life” talks about getting rid of your attachment to sins. You don’t want to just avoid sin, but you want to be disgusted by sin. He mentions that some people although they avoid sin they still have an attachment to it and they crave it, and are jealous of those who commit it and would commit it themselves if it wasn’t a sin. For me, this was a difficult way to live with lust and I would have not been able to say no to the temptation if I stayed in that state myself. Thanks to the grace of God with enough prayer, the graces of confession, and deep thought on the church’s teaching and seeing the truth of how these people in these photos are being degraded it actually makes me a bit sad to see it happening today. I hope this helps.

I believe it is also a good idea when trying to understand why the church teaches something to see where that teaching comes from. I think sometime we see the Church like we see other people–we see the faults and not the working of the Holy Spirit behind her (or in people Christ in them). Some scripture that the Church draws from for her teaching and why she teaches these things as mortal sin (this is not a comprehensive list):

Gal 5:19-21
1 Cor 9-10
Gen 38:8-11 (also note that the Biblical penalty for not giving your wife children in the Old Convenant was public humility not death–Duet 25:7-10).

Yes indeed. That is what I was trying to say. :slight_smile:

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