There are restrictions involved in the use of anything that is truly good and holy, and sex is indeed good and holy. For example, your mother may have a necklace of pearls that is very expensive. There are restrictions on its use, no doubt. A mother would hardly allow her child to play with them outside. Similarly, the reason why there are so many restrictions on the use of the sex act is that sex is profoundly good; for the sex act is the act of marriage, and marriage is good and holy. Marriage is the foundation of the family, which in turn is the fundamental unit of society. To misuse and abuse the sex act is to abuse the marriage act; in short, it is to abuse marriage. Abusing marriage will have serious repercussions on your own marriage in the future. Make no mistake about it, there is a real connection between the widespread misuse of the sex act and the reality that currently one in two marriages end in divorce.
Marriage is a joining of two (male and female) into one flesh, one body, through a commitment in which the two establish one another as unique, irreplaceable, and non-substitutable. Marriage is unitive in so far as the two consent to be one body, that is, the two freely choose to give themselves entirely to one another. Now the self includes the body, as well as one's time. To give oneself to another entirely -- not partially -- is to commit one's life to the other.
Now marriage is not only unitive, it is also procreative. The procreative aspect of marriage follows from the unitive aspect, for the procreation of new life results from the union of the male seed with the female egg in the unitive act of sexual intercourse. It results, in other words, from their one flesh union; for the child is the fruit of the couple's one flesh union (how many of you have your father's eyes, your mother's nose, etc.,.).
What distinguishes human behaviour from the behaviour of brute animals is reason. Animals lack reason, and so they are governed by their instincts. If they have an urge to eat, they will eat. If they have an urge to mate, they will mate, regardless of the prospects of commitment, fidelity, a successful relationship, etc. Dogs and cats don't care about these things. Human beings, on the other hand, are not governed by instinct, and ought not to be governed by passion or feeling, but by their highest faculty, namely reason.
There are two types of goods that we ought to consider in order to make sense out of this issue: sensible goods and intelligible goods. Brute animals are motivated solely by sensible goods, that is, things pleasing to the senses. Now it is certainly possible for human beings to be motivated by sensible goods, but we are ultimately motivated by higher goods, namely intelligible human goods. These cannot be sensed by any of the five senses or any of the internal senses. For example, life, truth, beauty, leisure, sociability, friendships, marriage, religion, and integrity constitute the entire network of intelligible human goods. The senses cannot apprehend life, or truth, or beauty, or integrity. They are not sensible, they have no color, shape, size, taste, etc.,. They are intelligible to the human intellect and are desired by the will, not by the senses. A fully human act will be one ordered towards intelligible human goods, and a morally good action -- to make a very long story short -- is one that respects or reveres intelligible human goods.
The two aspects of the sex act (the unitive and the procreative) are, in fact, basic intelligible human goods. In other words, they are not sensible goods. Marriage or conjugal union has no color, shape, size, taste, etc.,. And neither is human life a sensible good (something that can be perceived by the senses). The unitive and procreative purposes of marriage are known not by the senses, but by the intellect and desired by the will, because they are intelligible human goods.
Consider the diagram below. You can see that the goods which constitute the sex act are in fact the goods of marriage. That is why the sex act is called the "act of marriage", or the "marriage act". In this act, the two become one flesh, one body.
---- Unitive (a joining of two into one flesh, one body)
---- Procreation (a community of life)
---- Unitive (a joining of two into one flesh, thus an expression of married love)
---- Procreation of New Life
1. MARRIAGE is a community of love and life.
2. LOVE and LIFE, like the wedding ring, form a circle that is indivisible.
Now, human happiness is nothing other than human well-being. Happiness is not pleasure. One may have many pleasures in life and yet remain profoundly unhappy. Happiness is a matter of choosing, not having (i.e., pleasures, money, fame, etc.). When a person chooses well, that is, on the basis of intelligible human goods, that person is on the road to genuine human happiness. Happiness is the state of integral human fulfillment, which is the integration, in one's self, of all the intelligible human goods that exist. The pursuit of pleasures does not bring about integral human fulfillment because there is a real distinction between sensible goods and intelligible goods. A person can have many pleasures in life, yet remain unhappy. Conversely, a person can have few pleasures in life, yet experience profound happiness, that is, a sense of well-being and integration.
Sex is indeed pleasurable, as is eating and drinking. But eating is not primarily for pleasure, but for the sake of preserving human life. Eating is an activity that serves an intelligible human good, namely life. And it is certainly a good thing that eating is pleasurable and that there is a hunger instinct. If a person never got hungry or had no desire to eat because eating was not particularly pleasurable, he'd probably rarely eat and become undernourished, and possibly die. Thus it is reasonable that eating is pleasurable. The same is true for sex. If it was not pleasurable, people wouldn't engage in sexual union and the species would likely die out.
Nevertheless, the purpose of sex is not pleasure, even though it is pleasurable. That this is true is rather easy to demonstrate. Consider two people (even a married couple), both of whom are having sex merely for the sake of pleasure.
Person A -- -- -- -- -> Person B -- -- -- -- -> Person A
* Person A is having sex for pleasure. Hence, Person B becomes a means to A's pleasure.
1. Human beings must never be treated as a means to an end.
If person A is having sex for pleasure, then person B is a means to that pleasure, which exists in person A. But treating a human person as a means to an end is never justified. A "means" is something that is used, such as a piece of chalk or a computer. But a human being must never be used as a means to an end. Things must be used, not loved; persons must be loved, not used.
It is good that sex is pleasurable, but the goodness of the sex act does not consist in its pleasure. The human goodness of the sex act consists in its unitive and procreative aspects. In the act of sexual union, the two become one flesh, one body, and this is precisely the definition of marriage. The sex act is an expression and celebration of marriage (the choice to be one flesh, one body until death separates the two). It is an expression of conjugal love. It is meant to be a loving act, an act that expresses total commitment, a total giving of oneself or one's entire body, that is, one's entire life.
An unmarried couple who engage in the act of sexual union have not made that commitment to be one flesh, one body. In the act of sexual union, they do not therefore express a conjugal commitment or conjugal love. There is presently no intention to be one body (married), and so there is no openness to procreation (unless the motive is simply to conceive a child deliberately out of wedlock, but this is another moral issue). That is why non-marital intercourse tends to be contraceptive. And so the act of non-marital intercourse lacks intelligible human goodness. It is not a unitive act, except physically. At worst, the two merely use one another as a means to an end. At best, they pursue the feeling or experience of conjugal intimacy without the reality of conjugal intimacy. This is somewhat like the drug user who pursues the feeling of having his life in order (all together) without the reality of an ordered life (having it all together). In short, premarital sex is a lying with one's body. The act expresses and symbolizes a total giving of oneself, yet the two have not given themselves entirely to one another in the commitment of marriage. What one says with one's body does not correspond to one's intentions.
But love is a willing of the other's good for the other's own sake, not for the sake of what he or she can do for me. It is not a feeling, nor is it necessarily willing that a person experience pleasure. Love is sober and intelligent, not sentimental. The mother who "loves her child so much" that she feeds him/her chocolate bars and jelly beans all the time does not have the strength of character and good sense to truly love. The loving mother will place all sorts of restrictions on her child and deny him/her all sorts of options - for his/her own intelligible goodness (health).
For the sake of an orgasm, the teenage boy is willing to allow the other to become a mother without a commitment on his part, and he is willing to allow a child to be conceived without a legal father. Hence, the fornicator is an unjust person. And since happiness is a matter of character (good character), the fornicator will not experience a sense of fulfillment in his sexual actions. In his frustration, he will tend to seek sexual experiences with other women in order to try to find what he is missing in his own sexual life. But he will not find it, because what he is missing is a genuine unselfish love of the other, that is, he is missing a spirit of sacrifice. Sacrifice -- never forget -- is the language of love. Selfishness has never brought happiness or a sense of peace to any human being. On the contrary, happiness is found in self-possession through virtue.
The mere experience of an orgasm is not a genuinely human act. Only when the sex act is the intentional pursuit of genuine human goods - the unitive good of marriage and the good of procreation - does it become a truly fulfilling act and a source of genuine human happiness.
Many young people ask whether masturbation is a sin, a serious sin, or morally wrong, etc.,. It is important to keep things in perspective here. First, adolescence, at least for boys, is the time of most easy arousal, that is, the sexual peak. This is a rather new drive that is experienced as powerful and at times might seem uncontrollable. It is not unusual for a teenage boy to masturbate. Statistics consistently reveal that masturbation happens more frequently among adolescent boys than girls. Let's just say that masturbation, in this light, is not the greatest sin in the world. This does not mean to suggest that masturbation is okay. Consider the following points.
Repeated action leads to habits, and we all know that habits are hard to break. The purpose of masturbation is to procure the experience of orgasm. In other words, the purpose is merely pleasure. But pleasure is not a basic intelligible human good. The purpose of the sexual act is union and procreation. In other words, the sexual act is relational, not solitary. But masturbation is solitary. It is sex for the self. It is sex that has the self at its center. In other words, it is self-centered. Self-centered actions are selfish. Thus, masturbation is selfish. That's the moral problem with it. Furthermore, it creates the habit of using one's sexual powers selfishly. When one is in a marital relationship, the tendency will be to use one's spouse as a means of sexual pleasure, because one has been habituated to using sex selfishly.
Again, it is not the worst sin that one can think of committing, nor is it something a teenage boy should be overly anxious about. Rather, one should take advantage of the Sacrament of Reconciliation in order to receive the graces necessary to eventually exercise control over one's sexual drive. That really is the goal here, to achieve a certain level of moral development, which involves control over one's passions. The morally and psychologically healthy situation is that in which one is in control of one's drives and urges, as opposed to the situation in which our drives are in control of us. This is slavery, not moral liberty. Furthermore, control does not mean suppression. One should not suppress one's sexual drive, which amounts to denying it, refusing to face it, refusing to affirm it and recognize its goodness. One should recognize it, affirm it, be aware of its goodness, but also recognize the purpose of one's sexual powers and allow them to be perfected by reason. As psychiatrist Conrad Baars points out, the human emotions have an innate need to be guided by reason. Emotional health can only be achieved by affirming and directing our passions according to the demands of reason. That is the essence of virtue.