Chastity is not so much a negative virtue, but a positive affirmation of the inestimable dignity and value of one’s beloved. Chesterton's quote above illustrates this. Chastity certainly includes avoiding sexual wrong because this diminishes oneself and one’s partner and authentic love can take no part in that. But is so much more; it is a willingness to die for the sake of the beloved. Chastity is an expression of martyrdom by which one is willing to die to his disordered passions to witness to his future spouse and to the world the sacrificial love. This is the heroism every man wishes to live up to.
So, we can see why chastity is an irreplaceable virtue for authentic relationships of love. Unchaste couples will have a significantly greater likelihood of relationship conflict as well as broken relationships than those who practice chaste courtship and betrothal. This will be true before and after the wedding. The reason is that unchaste couples, even if unwittingly, are “using” each other to fill emotional desires such as pleasure, bonding, self-affirmation, a (false) sense of control over another, or control over one’s own life. Sexual use of another person is never for the good of another. To engage in sexual acts that are not within marriage and so ordered to the nature of sexuality (i.e. mutual selfless love and simultaneously, procreation) is always “use.” Those who do practice chastity are training themselves to master their passions and to say “no” to selfish inclinations. Self-mastered couples are able to pursue freely, the authentic good of their beloved. This is true love and it is the only love that can satisfy our deepest longings. Chastity is the school of self-mastery practiced in all successfully, intimate relationships.
Chastity must be developed as a “second nature” within each person if a couple’s relationship is to grow to its intended potential of authentic intimacy. Authentic intimacy itself is a measure of the degree of selfless of love each partner develops for the other. All virtues are habits; that is, they are attained and strengthened through constantly and consistently, willfully choosing of the authentic good associated with the particular virtue.
The authentic good associated with chastity is sexual activity properly ordered to communion and to procreation. The virtue of chastity includes the requirement to affirm the good of the other person, including his sexual value. However, it refuses to reduce him to his sexual value. Chastity means practicing the heroic choice to safeguard the purity of the other person, waiting for marriage to engage in what after all is rightly called “the marital act” the coming together of the two spouses in a union of one flesh.
Chastity purifies the intentions
This saying “yes” to the other person’s true good, which includes saying “not yet” to engaging in the act reserved to spouses, strengthens one’s “muscles” involved in the virtue of chastity. Chastity in courtship, betrothal and married life is exercising the will in a way analogous to physical exercise. Just as physical exercise has the effect of strengthening the body’s muscular strength, flexibility and aerobic capacity, moral exercise strengthens and purifies the will. It strengthens and purifies authentic love.
Chastity permits each person to say “no” to his selfish desires so he becomes free to say “yes” to the authentic good his lover. Consistently acting in this way purifies his love for his beloved. It allows one’s love to be more and more selfless. It exhibits an authentic concern for the other’s well integral wellbeing—body and soul. The exercise of chastity allows one to purify his intentions toward his beloved and to love her heroically, a love alone that can satisfy the heart’s longing.
Chastity refuses to reduce the other
The virtue of chastity gives one the freedom, or the “will power,” to refuse to reduce one’s beloved to his sexual value. It permits one to develop a love that refuses to use the other. Chastity demands that we build the habit of seeing the other in her sexual value, as a complete person created for her own sake. This practice of chastity will endow us with the self-mastery and spiritual maturity to make this love possible and from it we will experience the fruit of self-possession and joy.
Chastity aids in developing self-mastery
Self-mastery is an indispensable pre-requisite for authentic love. In our fallenness, concupiscence introduces a conflict between our natural desire to love the other for his own sake, and our concupiscent desire to possess him and to use him selfishly. For this reason, self-mastery is intimately united to the ability to love authentically. Self-mastery is not love though it cannot be fully developed without love. Self-mastery allows one to more and more freely choose the good of chastity and the other virtues, but without the choice of chastity and love, self-mastery will not grow. Love and self-mastery go hand-in-hand.