About sexual thoughts and fantasies inside and outside of the marital act
It is of the Divine law that a person may never willfully entertain sexual thoughts in his mind, even about his wife, outside of the marital act. The only sexual act the Church allows is the normal, natural, and procreative marital act. Everything else is contrary to the only primary end or intent of the sexual act—the procreation of children. If a person willfully entertains sexual thoughts outside of the marital act or unnecessarily puts himself into sexual temptations when there is no need to, he or she commits a mortal sin. Consequently, one may not even entertain or consent to sexual thoughts about one’s own wife or husband outside of the marital act, but must resist these thoughts or temptations as one would resist the thought of adultery or fornication: “Several doctors [of Divinity] maintain that willingly fostering wicked carnal thoughts in order to enjoy oneself is a deadly sin, even without doing the deed. Be sure, however, that kisses, gazes, and fondling, mainly caused by such wicked and lustful thoughts, without anything more, is an even greater sin. … it is even worse if these kisses do not respect the honesty which is usually kept in public.” (Jean Gerson, Oeuvres Complétes)
Athenagoras the Athenian (c. 175 A.D.): “But we [Christians] are so far from practising promiscuous intercourse, that it is not lawful among us to indulge even a lustful look. “For,” says He [Christ], “he that looks on a woman to lust after her, has committed adultery already in his heart.” [Matthew 5:28] Those, then, who are forbidden to look at anything more than that for which God formed the eyes, which were intended to be a light to us, and to whom a wanton look is adultery, the eyes being made for other purposes, and who are to be called to account for their very thoughts, how can any one doubt that such persons practice self-control?” (A Plea for the Christians, Chapter XXXII.--Elevated Morality of the Christians)
Simply said, women or men are not toys, playthings, or “bunnies” from which to derive sexual stimulation. When women or even one’s own wife are used in sexual fantasies, they are sexually abused, even if they are untouched. Many men rape many women each day and commit adultery, fornication and illicit sexual acts without laying a hand on them. Women also rape men and commit adultery, fornication and illicit sexual acts in this way. These rapes, fornications, illicit sexual acts and adulteries are not marked by physical violence but by psychological warfare. Because a person is often unaware of being used and abused, and because the abuser often does not fathom the real extent of the severity of his crime, this makes these mental and visual rapes/abuses/sexual crimes seem less devastating. Nevertheless, grave sin with all its degradation and death is being committed.
For instance, it would be quite sick for a husband not to resist sexual thoughts about his wife or to continually entertain such thoughts while at work or while on a trip, because while at work or while on a trip there is no chance for him to lawfully quiet his concupiscence and perform the marital act for procreational purposes. That’s why dwelling on such thoughts only would distract him spiritually and temporally and could even lead him into committing other sins, such as masturbation or adultery (in thought as well as in deed). All who do not wish to be damned must thus resist sexual thoughts and temptations outside of the marital act and may not entertain them in anyway.
It is of course one thing to be tempted to have sexual relations with one’s own wife or someone else (which is not sinful) and a whole other thing to consent to having sex with them in one’s thought or mind (which is sinful). Thus, a husband and wife may never consent to any sexual thoughts or fantasies about their spouse outside of the normal and natural marital act. However, that is not to say that it’s licit to think about bad or illicit things or give consent to them during the marital act—as so many evil and heretical people and so-called theologians actually teach today—for that is not what it means. What it means is simply that a person can only fully consent to, and give way to, sexual thoughts and desires (about their spouse) during the sexual act without committing any sin, so long as these thoughts range within what is lawful, natural, reasonable and necessary for the completion of the marital act to occur.
St. Thomas Aquinas wonderfully explains this thought process further to us in his Summa:
“Accordingly a man who is thinking of fornication, may delight in either of two things: first, in the thought itself [by merely thinking about it but not necessarily giving consent to it or the pleasure derived from it], secondly, in the fornication thought of. Now the delectation [pleasure] in the thought itself results from the inclination of the appetite to the thought; and the thought itself is not in itself a mortal sin; sometimes indeed it is only a venial sin, as when a man thinks of such a thing for no purpose; and sometimes it is no sin at all, as when a man has a purpose in thinking of it; for instance, he may wish to preach or dispute about it. Consequently such affection or delectation [pleasure] in respect of the thought of fornication is not a mortal sin in virtue of its genus, but is sometimes a venial sin and sometimes no sin at all: wherefore neither is it a mortal sin to consent to such a thought [it only becomes a mortal sin if one consents to and wants to have the illicit pleasure in the thought]. In this sense the first opinion is true. But that a man in thinking of fornication [or other unreasonable or sinful sexual acts] takes pleasure in the act thought of, is due to his desire being inclined to this act. Wherefore the fact that a man consents to such a delectation [pleasure], amounts to nothing less than a consent to the inclination of his appetite to fornication [or other sinful sexual acts]: for no man takes pleasure except in that which is in conformity with his appetite. Now it is a mortal sin, if a man deliberately chooses that his appetite be conformed to what is in itself a mortal sin. Wherefore such a consent to delectation [or pleasure] in a mortal sin, is itself a mortal sin, as the second opinion maintains.” (St. Thomas Aquinas, Summa Theologica, First Part of the Second Part, Q 74, Art. 8)
Thus, if even pleasurable sexual thoughts outside of the marital act of one’s own legitimate spouse is sinful if not fought against, how much more must not the sensual thoughts of one’s neighbor be? If even kisses between married spouses for the purpose of carnal pleasure is condemned as a mortal sin by the Catholic Church, how much more must not the perversions of the marital acts be that so many spouses today practice? “For to Christians this rule of life is given, that we should love the Lord Our God with all the heart, with all the soul, and with all the mind, and our neighbor as ourselves... God alone, to find whom is the happiest life, must be worshiped in perfect purity and chastity... in chaste and faithful obedience, not to gratify passion, but for the propagation of offspring, and for domestic society.” (St. Augustine, On the Morals of the Catholic Church, Chapter 30, Section 62, A.D. 388)
St. Alphonsus, Precepts of the Decalogue, Chapter VI, The Sixth and Ninth Commandments: “1. WHAT IS ONE OBLIGED TO CONFESS IN THE MATTER OF IMPURITY?
“I will only observe here, in general, that it is necessary to confess not only all the acts, but also improper touches, all unchaste looks, all obscene words, especially when spoken with pleasure, or with danger of scandal to others. It is, moreover, necessary to confess all immodest thoughts.
“Some ignorant persons imagine that they are bound only to confess impure actions: they must also confess all the bad thoughts to which they have consented. Human laws forbid only external acts, because men only see what is manifested externally; but God, who sees the heart, condemns every evil thought: “Man sees those things that appear; but the Lord beholdeth the heart.” (I Kings, xvi. 7.) This holds good for every species of bad thoughts to which the will consents. Indeed, whatever it is a sin to do, it is also in the sight of God a sin to desire.
“2. WHAT DISTINCTION IS TO BE MADE IN REGARD TO BAD THOUGHTS?
“I said, thoughts to which the will consents. Hence, it is necessary to know how to determine when a bad thought is a mortal sin, when it is venial, and when it is not sinful at all. In every sin of thought there are three things: the suggestion, the pleasure, and the consent.
“1. The suggestion is the first thought of doing an evil action that is presented to the mind. This is no sin; on the contrary, when the will rejects it we merit a reward. "As often," says St. Antonine, "as you resist, so often you are crowned." Even the saints have been tormented by bad thoughts. To conquer a temptation against chastity, St. Bernard threw himself among thorns, St. Peter of Alcantara cast himself into an icy pool. … St. Catharine of Siena was once assailed by the devil for three days with impure temptations; after the third day our Lord appeared to her in order to console her. She said to him: "Ah, my Saviour, where hast Thou been these three days?" He replied: "I was in your heart to give you strength to resist the temptation by which you were attacked." He then showed her that her heart had become purer than it was before.
“2. After the suggestion comes the pleasure. [Generally] When a person is not careful to banish the temptation immediately, but stops to reason with it, the thought instantly begins to delight him, and give him pleasure, and thus draws the person on to give his consent to it. As long as the will withholds the consent, the sin is only venial, and not mortal. But if the soul does not then turn to God, and make an effort to resist the pleasure, it will easily go on to give its consent. "Unless," says St. Anselm, "a person repel the pleasure, it passes into consent, and kills the soul." A woman who had the reputation of a saint was tempted to sin with one of her servants; she neglected to banish the thought instantly, and so in her heart consented, and fell into sin, but only in thought. She afterwards fell into a more grievous sin, for she concealed in confession the complacency she had taken in the bad thought, and died miserably. But because she was believed to be a saint, the bishop had her buried in his own chapel. On the morning after her burial she appeared to him, enveloped in flames, and confessed, but without profit, that she was damned on account of the bad thought to which she had consented.
“3. The soul loses the grace of God and is condemned to hell the instant a person consents to the desire of committing sin, or delights in thinking of the immodest action as if he were then committing it. This is called morose delectation, which is different from the sin of desire.
“My dear Christians, be careful to banish these bad thoughts, by instantly turning for help to Jesus and Mary. He who contracts the habit of consenting to bad thoughts exposes himself to great danger of dying in sin, for the reason that it is very easy to commit sins of thought. In a quarter of an hour a person may entertain a thousand wicked desires, and for every evil desire to which he consents he deserves hell. At the hour of death the dying cannot commit sins of action, because they are unable to move; but they can easily indulge sins of thought, and the devil suggests every kind of wicked thought and desire to them when they are in that state. St. Eleazar, as Surius relates, was so violently and frequently tempted by bad thoughts at the hour of death, that he exclaimed: "Oh, how great is the power of the devils at the hour of death!" The saint, however, conquered his enemies, because he was in the habit of rejecting bad thoughts; but woe to those who have acquired a habit of consenting to them! Father Segneri tells us of a man who during his life had often consented to bad thoughts. At the hour of death he confessed his sins with great compunction, so that every one regarded him as a saint; but after death he appeared and said that he was damned; he stated that he made a good confession, and that God had pardoned all his sins; but before death the devil represented to him that, should he recover, it would be ingratitude to forsake the woman who loved him so much. He banished the first temptation: a second came; he then delayed for a little, but in the end he rejected it: he was assailed by a third temptation, and consented to it. Thus, he said, he had died in sin, and was damned.” (The complete ascetical works of St. Alphonsus, vol 15, pp. 466-469)