Rambam, consistent with his worldview, sees bodily needs and pleasures as mere means to the ultimate end – spiritual service of God. Nevertheless, God created flesh-and-blood human beings, who must take very good care of their bodies, since it is the vehicle which allows them to study Torah and fulfill mitzvot. If a person does not take care of bodily needs, including the natural desire for sexual intercourse, it will cause deterioration of physical and mental health and loss of equilibrium. Such a person will be unable to concentrate on spiritual service. The purpose of the mitzva of marriage and the sexual prohibitions is to train every person to satisfy their natural desire for physical intimacy within the framework of halakha. The more careful one is to satisfy his own needs and those of his spouse without getting overwhelmed by physical lust, the more sanctified such a person becomes. This is the aim of the mitzva of ona: to satisfy natural sexual desire, each person according to their health and occupation, no more and no less.
When a person follows this path, then even tending to one’s physical needs is considered part of divine worship:
When he has sexual intercourse, his only intention should be to keep his body healthy and produce viable offspring…. One who follows this path for his entire life serves God constantly, even while doing business and even while having sexual intercourse. For his intention is always to provide for his needs so that his body is whole, in order to serve God…. This is what our Sages meant when they commanded, “All of your actions should be for the sake of heaven” (Avot 2:12). This is also what Shlomo said, in his wisdom (Mishlei 3:6): “In all your ways, know Him, and He will make your paths smooth.” (MT, Laws of Dispositions 3:2-3).
Rambam thus disagrees with the gentile sages who praise celibacy, because he feels that it is unnatural, painful, and unhealthy. Just as we do not encourage a person to starve himself on a regular basis or to suppress his need to relieve himself, so too, we must not encourage a person to abstain from sexual relations. Even if the person’s spouse is willing, as long as abstention involves going against natural desires, they must satisfy those urges. However, since sexual relations are merely a means to an end, one should not indulge in them more than necessary. One who indulges in physical pleasures more than necessary to serve God is like an animal that always follows its natural impulses. From this perspective, “Our sense of touch is a disgrace to us” (Moreh Nevukhim II:36).
It stands to reason that the more a person is engrossed in Torah, the less he will feel this need. This is virtuous, as long as husband and wife develop this virtue in tandem. However, when one spouse has a palpable need for sexual intimacy, no attempts should be made to suppress it, for doing so will demand a constant fight against the urges. Instead of developing spiritual virtues, that spouse will be preoccupied with doing battle against the body. Not only that, but there is concern that such a person will delude himself into thinking that he has been liberated from the burden of his urges, but ultimately the repressed urges may find unrestrained expression and lead to sexual transgression. Even if he does not end up sinning, all the effort that he exerts to restrain his urges will warp his spirit and damage his mental health. The Torah therefore gave us the mitzva of ona with all its parameters, so that husband and wife, by observing halakha, will treat each other and their own bodies properly.
The advantage of Rambam’s approach is that one who follows it will not engage in self-delusion, will not try to be overly abstemious while imagining that he has successfully overcome his physical needs and ascended to the lofty virtues of asceticism and sanctity. But neither will he fool himself into constant indulgence of the body and the passions with the claim that he is “sanctifying the material” and “redeeming sparks of holiness.” The drawback of this approach is that it denies any intrinsic value to the body and the act of sexual intimacy.
Realistic, critical, and intellectual individuals love Rambam’s approach because it does not pretend to sanctify what appears profane. But even the wider public has much to gain from his approach, as it recognizes human physical needs and does not attempt to deny human nature.
A person must direct his heart and all his actions only to knowing God. His sitting down, getting up, and speech must all be directed to this purpose…. Likewise when eating, drinking, and having sexual relations, his intention should not be only for his own gratification, which would lead him to eat and drink only what tastes sweet, and to engage in relations for pleasure only. Rather, when he eats and drinks, he should have in mind that he is doing so in order to keep himself healthy…. Similarly, when he has sexual intercourse, his only intention should be to keep his body healthy and produce viable offspring. Therefore, he should not engage in sexual relations whenever he desires to do so, but only when he knows that he needs a sexual release for his physical well-being or to produce viable offspring…. He should be mindful of having a son; perhaps he will become a Torah scholar or a Jewish leader. Thus, one who follows this path for his entire life serves God constantly, even while doing business and even while having sexual intercourse…. (MT, Laws of Dispositions 3:2-3)
As is known, young people have a more frequent need for sex – two or three times a week – but among older people, it decreases to once a week, and among the elderly, even less frequently. Of course, these are generalizations; some individuals need more, and some less.
Elsewhere, Rambam writes:
A man’s wife is permitted to him; therefore, whatever a man wishes to do with his wife, he may do. He may have sexual relations with her anytime, kiss any body part that he wants, and penetrate her vaginally, anally, or through another body part. Nevertheless, it is the practice of the pious to avoid acting frivolously in such matters. Rather, he should sanctify himself during sexual intercourse, as explained in Laws of Dispositions. He should not deviate from normal behavior and practice, as this is meant only for procreation…. The Sages disapprove of one who has relations frequently and constantly cohabits with his wife like a rooster. It is deeply flawed, the conduct of the unrefined. (MT, Laws of Sexual Prohibitions 21:9, 11)
Thus, on one hand, Rambam praises those who minimize sexual relations, but on the other hand, he does not try to restrain natural human desire. See Harḥavot.
We must, of course, add that even if asceticism suits the husband’s body and temperament, if his wife remains interested, he is still obligated to please her sexually. As Rambam writes: “The ona mandated by the Torah depends on each man’s stamina and occupation…. A wife may prevent her husband from traveling for business except locally, so that he does not withhold her ona, and he may not travel without her permission…” (MT, Laws of Marriage 14:1-2). Additionally, “A man who decreases the frequency of sexual relations is praiseworthy, as long as he does not neglect the set ona without his wife’s consent” (MT, Laws of Sexual Prohibitions 21:11). The same applies when asceticism suits the wife but not the husband; she may not neglect ona without his consent.