With the increased use of NFP in recent decades the Church has discovered that the informed practice of NFP actually builds virtue. In other words, couples who have used NFP become unselfish by using NFP properly. Thus, the Church has learned that if authentic virtue is weak or absent at the beginning, using NFP properly instills it! Love is a choice in one’s will to give oneself to another. But that choice is founded on the recognition of the dignity of the other as well as the dignity of oneself (who would give oneself to another if one thought the gift worthless?). Therefore, anything which leads to a greater appreciation of the dignity and value of human beings fosters love.
The human body is the expression or manifestation of the human person. John Paul II speaks of the body as revealing the person and when we express God-like acts through the body, the body is actually a physical image of God. Pope John Paul II goes so far as to say that the human body speaks a language. (Theology of the Body series, as well as Familiaris Consortio.) Since we are created to act as God acts, and He LOVES, we are created to love as He does. Since we have bodies, and we express our acts in and through our bodies, God gave us a means of expressing love physically. Since true, authentic love is THE most God-like act possible for human beings (because it is the most God-like act), and since the body has the possibility of expressing this love, the study of those powers of the body through which we can express an intimate self-giving love will reveal more about the person and even about God than the study of other aspects of the human body.
NFP is the study and knowledge of the bodily powers through which we bodily express conjugal love. NFP, therefore, reveals the dignity of both spouses to one another. In revealing this awesome dignity, it fosters love as well as a deep and abiding respect in each spouse for himself or herself and for the other. It also builds an unbelievable longing to share the infinite goods of human life with others, i.e., with children. NFP then builds a respect for human life. With this respect in place through the use of NFP, any decision by a couple to try to achieve a pregnancy or to avoid will be made for a good reason. It is not that serious reasons are not necessary—they are. But, a couple practicing NFP after taking the classes and knowing the method, practicing their faith attending Church and receiving the sacraments, with an active prayer life, and conscientious about the religious education of their children, will, if they decide to avoid a pregnancy, have serious reasons. This is what was meant by saying that virtue results from using NFP. It should also be noted that NFP couples generally discuss whether or not to try to achieve a pregnancy every single month. This re-examination also builds a respect for life.
