The Doctrine of The Catechism of St. Thomas Aquinas

We return to a central question: what would St. Thomas say about NFP? Several distinctions must be made before providing an answer, after which we will consider the recent magisterial literature and then find a solution for how to reconcile St. Thomas with common teaching. We look now at the text of The Catechism of St. Thomas Aquinas on the use of sex within marriage.

Moreover, it must be known that the Commandment, “Thou shalt not commit adultery,” not only forbids adultery but also every form of immodesty and impurity. There are some who say that intercourse between married persons is not devoid of sin. But this is heretical, for the Apostle says: “Let marriage be honorable in all and the bed undefiled.” (Hebrews 13:4) Not only is it devoid of sin, but for those in the state of grace it is meritorious for eternal life. Sometimes, however, it may be a venial sin, sometimes a mortal sin. When it is had with the intention of bringing forth offspring, it is an act of virtue. When it is had with the intent of rendering mutual comfort, it is an act of justice. When it is a cause of exciting lust, although within the limits of marriage, it is a venial sin; and when it goes beyond these limits, so as to intend intercourse with another if possible, it would be a mortal sin.^{58 58} The Catechetical Instructions of St. Thomas Aquinas, p. 80; trans. Collins, Joseph (1939), made available online by The Catholic Primer, 2004. Cf. ST Suppl., q. 49, a. 4; see also Commentary on 1 Corinthians, §328-329, which reiterates largely the same doctrine.

There are these four categories of the use of the marriage bed: virtue, justice, venial sin, and mortal sin.

First there is “virtue,” which is dependent upon direct or “actual” or at least “virtual” procreative intention willed in an act of intercourse.⁵⁹ The generosity of the spouses towards the possibility of receiving children and thus building up the community and raising souls to love and serve God is thereby manifested, making it “virtuous.” ⁵⁹ I take here Fr. John Hardon, SJ’s definition of “virtual intention,” aware that there could be other ways to define the term. “An intention that was once made and continues to influence the act now being done. But it is not present to the person’s consciousness at the moment of performing the act. This kind of intention is sufficient for a human act to be voluntary and therefore morally responsible.” See “Virtual Intention,” John Hardon’s Modern Catholic Dictionary (Eternal Life), https://www.catholicculture.org/culture/library/dictionary/index.cfm?id=37121. To interrupt or stop a virtual intention towards children in one’s use of marriage would require some positive mental act or desire for such interruption, even if only vaguely.

Second, and most interestingly for us, there is “justice,” which is the case of the marital debt. The text here does not give a detailed explanation of the marital debt the way the Commentary on the Sentences does. A plain reading of the text, however, in particular due to the word “mutual” in the phrase “rendering mutual comfort,” implies that the request to have one’s concupiscence calmed is just insofar as it requests what is rightfully one’s own, which is the spouse’s body in marital union. It could be imagined here that such union is the due means of the preservation of oneself from the possibility of illicit sexual activity or even merely from annoying distraction from the normal pursuit of rational and social goods; to give this to one’s spouse is righteous, for the preservation of one’s spouse from sin and assisting him or her in pursuit of holiness is one of the main purposes of the sacrament of Matrimony. The one who renders the comfort is also comforted him or herself, thus contributing to the overall psychological health and friendship of the spouses. However, this is a deliberate eisegesis – it is quite clearly at odds with St. Thomas’s intention. If he was disagreeing with his previous teaching on this point, we would expect him to be clear about it.

Third there is “venial sin,” which is mere pleasure seeking (contradistinguished from the need to pay or receive the debt and also from the intention towards procreation), and fourth there is “mortal sin.” These two cases are explained in the Commentary on the Sentences in the following way:

[If] pleasure be sought in such a way as to exclude the honesty of marriage, so that, to wit, it is not as a wife but as a woman that a man treats his wife, and that he is ready to use her in the same way if she were not his wife, it is a mortal sin; wherefore such a man is said to be too ardent a lover of his wife, because his ardor carries him away from the goods of marriage. If, however, he seek pleasure within the bounds of marriage, so that it would not be sought in another than his wife, it is a venial sin.^{60 60} ST Suppl., q. 49, a. 4.

The case of venial sin in relation to the case of “justice” is what is most interesting for us in our inquiry. The meaning of “seeking pleasure” seems to indicate the use of sex to “recreate” within the bounds of marriage, and this must also in fact imply an absence of an actual or virtual procreative intention, or else it would be in the category of “virtue.” In fact, “sexual recreation” is the very same “excitement of lust” which is spoken of in the Catechism text quoted above, and it is treated in the Commentary on the Sentences as a movement based on sexual appetite as opposed to a movement of reason which would entail virtue.⁶¹ This sort of sexual activity is an unnecessary and therefore demeritorious momentary inhibiting of the powers of reason and a movement toward the creation of a habit of such activity, together with the onset of a general dulling of the spiritual senses over time.⁶² Thus it is not eutrapelia either, which merely relaxes the mind through recreation but does not make one lose the power of reasoning altogether as does sexual union.⁶³ Any social goods which such recreational sexual activity can produce in the couple can and should be pursued by other means – and St. Thomas was certainly not unaware of the social or psychological benefits of conjugal activity, which point functions as the anchor for the contrary argument today, insofar as an argument is even made.^{64 61} Ibid. ⁶² See ST II-II q. 153, a. 2, ad. 1; a. 5. ⁶³ ST II-II q. 168 a. 2 resp. ⁶⁴ See SCG III ch. 123, 6: “Furthermore, the greater that friendship is, the more solid and long-lasting will it be. Now, there seems to be the greatest friendship between husband and wife, for they are united not only in the act of fleshly union, which produces a certain gentle association even among beasts, but also in the partnership of the whole range of domestic activity. Consequently, as an indication of this, man must even ‘leave his father and mother’ for the sake of his wife, as is said in Genesis (2:24). Therefore, it is fitting for matrimony to be completely indissoluble.” St. Thomas Aquinas, Summa Contra Gentiles, ed. Joseph Kenny; trans. Vernon Bourke; (Hanover House: New York, 1955-1957).

It is clear that for St. Thomas it is always a venial sin to request the debt, unless this be for the sake of procreation, and the spouse is morally obliged to pay the debt, even if the spouse does not presently wish to have children. St. Thomas would say that the one requesting the debt outside of this purpose would be owed its payment by strict or legal debt, and that this is simply a bad use of what one is owed by justice. Only the gravest sort of reason would allow for a spouse to withhold the payment of the debt; the analogy which comes to mind is the example St. Thomas gives of the rebel who wishes to claim his deposited sword, which return may be refused him.^{65 65} ST II-II, q. 120, a. 1; the treatment of the “bottom line” regarding cases of requesting and refusing the marital debt goes beyond the scope of this book. St. Thomas does treat the issue at some length in the Commentary on the Sentences.

While interiorly coherent reasoning, one is still left with the sense that this treatment simultaneously overstates the claim a spouse has on the other’s body (viz., to use it for one’s sin), and underappreciates the utility of the use of marriage in easing concupiscence insofar as marriage and its act exist secondarily for this end. Yet we should not easily stray from the teaching of St. Thomas, and indeed we see that some have clearly gone too far.

Some contemporary authorities, such as those seeking to popularize and promote the teachings of St. John Paul II on human sexuality, might even go so far as to imply that the marital act is a spiritual act or experience, which is utterly foreign to the thought of St. Thomas and to the general moral-ascetical-mystical tradition.⁶⁶ On the contrary, it is noted by Pius XII that the use of mutual abstinence in marriage is helpful for freeing oneself for prayer in a way that is superior to the habitual use of marriage.⁶⁷ Thus we can certainly understand the conclusion of St. Thomas that the desire to use pleasure in the marital act (and to use the marital act itself) is legitimate only when annexed to the payment of the marital debt or to an intention to conceive children by the sexual act, especially given that this is rooted so deeply in the teaching of St. Augustine.⁶⁸ Besides, the more one enjoys an act chosen under the impulse of reason as opposed to passion, the more virtuous that act will be, as one is desiring it with his whole self, rather than forcing a part of himself by a kind of violence.^{69 66} ST II-II, q. 186, a. 4: “The religious state requires the removal of whatever hinders man from devoting himself entirely to God’s service. Now the use of sexual union hinders the mind from giving itself wholly to the service of God, and this for two reasons. First, on account of its vehement delectation, which by frequent repetition increases concupiscence, as also the Philosopher observes (Ethic. iii, 12): and hence it is that the use of venery withdraws the mind from that perfect intentness on tending to God. Augustine expresses this when he says (Solil. i, 10): ‘I consider that nothing so casts down the manly mind from its height as the fondling of women, and those bodily contacts which belong to the married state.’” (The second reason is related to the preoccupation of caring for one’s household, which arises from marriage and offspring.) See also ST Suppl., q. 41, a. 3, ad. 3. ⁶⁷ Pope Pius XII, Sacra Virginitas (Vatican City: Libreria Editrice Vaticana, 1954) §38: “Or rather does not the Apostle Paul admit [1 Cor. 7:5] that they have the right of abstaining for a time from the use of marriage, so that they may be more free for prayer, precisely because such abstinence gives greater freedom to the soul which wishes to give itself over to spiritual thoughts and prayer to God?” ⁶⁸ Following on the analogy with communication, an analogy with digestion could also be made, namely, that to eat only for pleasure without any bodily benefit foreseen, i.e., intentional overeating, would also be sin. See ST II-II q. 148, and SCG III ch. 127, 1. However, the digestive faculty is not structured entirely the same way as the sexual faculty, and this analogy faces the similar problems which are explored in Chapter Three with regards to solam voluptatem. ⁶⁹ ST I-II, q. 24, a. 3, ad. 1.

The exegesis of St. Thomas is simple enough, but the major question which remains for us is this: can the request for the marital debt be licit without at least a virtual intention towards having children?

If we follow the line given in the Commentary on the Sentences, the answer is clearly “no” – an actual or at least a virtual intention is required in favor of children, the bonum prolis, in every sexual act initiated on the part of both spouses, or else there is sin, including making the request for the marital debt (but not in fulfilling the duty of paying it). This is also essentially the doctrine St. Thomas gives in the Commentary on 1 Corinthians. This line would certainly exclude NFP used in favor of preventing conception.

However, for the recent magisterial literature the answer very much seems to be “yes,” even though it does not ever address the “request for the debt” as such; if mapped onto the doctrine of the Catechism of St. Thomas we would probably want to say “yes” because it is still a matter of justice, namely, asking for what one is due.⁷⁰ We can see a pathway through to accepting the liceity of NFP as a recourse to infertile periods while still substantially saving the teaching of St. Thomas, though the doctrine we find in the Commentary on the Sentences and earlier literature on the request for the marital debt being necessarily sinful absent a virtual or actual procreative intention would need to be abandoned. (I have already made a brief argument that the strength of St. Thomas’ argument – which is a summary of all the arguments of earlier authorities, especially St. Augustine – is less than what we would expect, including in terms of Biblical exegesis – commutative justice renders what is due. The claim that it is due by “concession” or is necessarily a sinful “superfluity” is simply not as robust a case as St. Thomas normally makes.⁷¹) ⁷⁰ It is perhaps worth noting that St. Thomas never addresses the issue of the marital debt in the Summa Contra Gentiles or other writings in the way that he does in the Commentary on the Sentences. He does address it at some length in the Commentary on 1 Corinthians. ⁷¹ Those tempted to take the pure Thomistic line here are urged to be cautious, not only for the problem stated with the intrinsic weight, but also due to the extrinsic weight of the tradition after St. Thomas, including St. Alphonsus (who makes a similar exegesis on 1 Corinthians 7:6-7 as myself in De Matrimonio, §882,) and several popes, as we will see. One obscure but helpful manual which gives an argument against the Augustinian-Thomistic line is Reiner Sasserath, Cursus Theologiae Moralis, vol. 4, p. 491 (1771). He argues that, since marriage was instituted partly to help one avoid fornication, to hold that requesting the debt is immoral would actually be counterproductive – it would be a “laqueus animarum,” a “snare of souls.” He does, however, uphold a sensible reading of Innocent XI’s condemnation (which we will read momentarily), arguing that pleasure is ordered to procreation and that therefore inverting this order, while remaining an act licit in itself, involves a perverse will, thus rendering the act a venial sin. Sasserath does, however, against St. Alphonsus, think that health alone is a sufficient motive for the marital act.

However, this still does not necessarily mean that the marital act, in the context of NFP used to avoid pregnancy, does not require any special justification of its own. This remains yet to be seen, and I will argue that when intentionally avoiding pregnancy the marital act does indeed require a special motivation to avoid venial sin.