You miss the point entirely. Look especially at the sentence before his conclusion: “Now lust consists essentially in exceeding the order and mode of reason in the matter of venereal acts.” Read Article 1, too. It’s the fact that lust goes beyond right reason that makes it a sin. It’s clear that St. Thomas recognizes that marital intercourse does not necessarily involve the wantonness or debauchery that constitute lust.
St. Thomas says in Article 2:
Reply to Objection 2 – That venereal concupiscence and pleasure are not subject to the command and moderation of reason, is due to the punishment of the first sin, inasmuch as the reason, for rebelling against God, deserved that its body should rebel against it, as Augustine says (De Civ. Dei xiii, 13).
Reply to Objection 3 – As Augustine says (De Civ. Dei xiii, 13), “the child, shackled with original sin, is born of fleshly concupiscence (which is not imputed as sin to the regenerate) as of a daughter of sin.” Hence it does not follow that the act in question is a sin, but that it contains something penal resulting from the first sin.
But what does St. Augustine say in one of the chapters of City of God preceding the one just cited twice by St. Thomas?
…lust not only takes possession of the whole body and outward members, but also makes itself felt within, and moves the whole man with a passion in which mental emotion is mingled with bodily appetite, so that the pleasure which results is the greatest of all bodily pleasures. So possessing indeed is this pleasure, that at the moment of time in which it is consummated, all mental activity is suspended. What friend of wisdom and holy joys, who, being married, but knowing, as the apostle says, “how to possess his vessel in santification and honor, not in the disease of desire, as the Gentiles who know not God,” would not prefer, if this were possible, to beget children without this lust, so that in this function of begetting offspring the members created for this purpose should not be stimulated by the heat of lust, but should be actuated by his volition, in the same way as his other members serve him for their respective ends? – Augustine, City of God 14:16
St. Augustine, then, clearly taught that lust accompanies
every instance of marital intercourse. St. Thomas doesn’t doubt this either, as his question, “Whether the lust that is about venereal acts can be a sin?” indicates. And according to St. Thomas, “…without any doubt lust is a sin.”
So, marital intercourse is one thing, and the lust that accompanies it and makes that intercourse physically possible is another. The act of marital intercourse itself can be accomplished without any
inherent sin if it is done with the sole intent of procreation, but the act of marital intercourse cannot be accomplished without the
accompanying sin of lust, since it is lust which necessarily enables the generative organs to fulfill their generative functions.
In summary, in searching for a proof that marital intercourse is inherently sinful, you’re barking up the wrong tree because neither St. Augustine nor St. Thomas believed that, nor have
I been arguing that myself (though perhaps I misspoke somewhere along the way and made you
think that – if that’s the case, then I apologize for not being more clear).
In case you don’t realize it, the CCC doesn’t supersede or revoke the earlier catechism. Both stand.
If the earlier argument still stands (which it doesn’t, as I hope to show later), then why isn’t it used anymore? Isn’t it because the use of the word “murder” in conjuction with non-abortive contraception (e.g., condoms, surgical procedures, ovulation-delaying drugs) is patently ridiculous? (Did you not see FM297’s outrage at the notion that contraception is murder?) And whether you call it “murder” or “conspiracy to commit murder” really makes no difference because you can’t conspire to murder someone who doesn’t exist!
Well, if you really want to get far-fetched, I suppose you
could conspire to murder somebody’s firstborn child, even if that somebody has yet to conceive any children. You could even make preparations to carry out this “hit” on a person who doesn’t exist yet. But this still wouldn’t be an actual crime until there was an actual victim. There would perhaps be a crime of
intent, I guess. But
Humanae Vitae says, “It cannot be denied that in each case * the married couple, for acceptable reasons, are both perfectly clear in their intention to avoid children and wish to make sure that none will result.” So if you’re going to ascribe “conspiracy to commit murder” (i.e., a crime of intent) to a couple using ABC, you’re going to have to ascribe the same crime to a couple using NFP. Is that really what you want to do?
–Mike*