In regards to one's own spouse of course.

Reading St Alphonsus Sunday sermon this week had me thinking 

Some young men will ask: Father, is it sinful to make love? I say: I cannot assert that of itself it is a mortal sin; but persons who do so are often in the proximate occasion of mortal sin; and experience shows that few of them are found free from grievous faults. It is useless for them to say that they neither had a bad motive nor bad thoughts. This is an illusion of the devil; in the beginning he does not suggest bad thoughts; but when, by frequent conversations together, and by frequently speaking of love, the affection of these lovers has become strong, the devil will make them blind to the danger and sinfulness of their conduct, and they shall find that, without knowing how, they have lost their souls and God by many sins of impurity and scandal. Oh! how many young persons of both sexes does the devil gain in this way! And of all those sins of scandal God will demand an account of fathers and mothers, who are bound, but neglect, to prevent these dangerous conversations. Hence, they are the cause of all these evils, and shall be severely chastised by God for them.

Above all, in order to avoid bad thoughts, men must abstain from looking at women, and females must be careful not to look at men

It is always dangerous to look at young persons elegantly dressed; and to look at them purposely, and without a just cause, is, at least, a venial sin.

is there a resource that explains what is or isn't permissible? I don't want people here to explain because this is a public forum and may cause scandal, but pointing me in the right direction would help.

Most traditional moral theology manuals treat the explicit characteristics of intimacy, but do so in Latin. 

In the strict order of things, any sɛҳuąƖ activity which doesn't complete in natural intercourse is gravely sinful. A liberal interpretation of this reality has led some to conclude that "anything goes" as long as the act completes in natural intercourse. I'm not convinced that's true. St Alphonsus, I've heard, regarded imperfect sodomy as a despicable act. I can't find a citation for that, maybe someone else can. But it sounds right to me.

I think the best advice comes from St Thomas Aquinas, who instructs husbands to treat their wives as their wives rather than as any woman. I think any man will intuitively understand that this means treating intimacy with a certain dignity that will preclude degrading and humiliating acts. And I think if a man asks himself "am I treating her as my wife or just as any woman?", he will instinctively know if he is acting properly. 

What if the man has a mindset that he wouldn't do such acts with any women except his wife?

I could be misunderstanding, but you sound like a melancholic getting lost in the weeds of his own thoughts. Go do something to clear your mind.

Moral theology : Jone, Heribert, 1885-1967 : Free Download, Borrow, and Streaming : Internet Archive

Not sure if it gives the whole book.  If not:

limited preview

What if the man has a mindset that he wouldn't do such acts with any women except his wife?

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He isn't treating his wife like his wife if he's treating her like a whore. 

If you aren’t married or at the very least engaged, you don’t need to know things like this. There’s a reason that moral theology isn’t taught until the end of seminary, it’s a delicate subject with some nuance involved.

Broadly speaking, I will say that the church has taught that Saint Alphonsus is safe to follow in ALL of his opinions, but even St Alphonsus admits that many of his opinions are just those, opinions and one would be safe to follow more permissive opinions of other moral theologians.

in any case, don’t concern yourself with things like this if you aren’t married or at least engaged. Just pray for a holy spouse.

^^^This^^^


I'd say, as long as you know how to avoid sin, you probably don't even need to know a single thing about how procreation works until you are about to marry. Anything else is just a way the devil gets you to dwell on dangerous topics.

limited preview

You can "borrow", so you you can read the whole book.

Useless curiosity, if I may say so.

When you get married, it is expected that you will have some sort of preparation. A good priest should conduct some classes on the subject, and you can always ask a good confessor a week before your marriage or so.

Don't rush.

You are better off concentrating on reading about how to be a good husband and father.

The above is very good advice. Wait until you are engaged to be married before you focus on the specific details of the marriage act.