[From "Natural Family Planning Is Evil"]

What is Natural Family Planning? Natural Family Planning (NFP) is the practice of deliberately restricting the marital act exclusively to those times when the wife is infertile so as to avoid the conception of a child. It is also called “the rhythm method.” NFP or rhythm is used for the same reasons that people use artificial contraception – to avoid the conception of a child while carrying out the marital act. Antipope Paul VI explained correctly that NFP is birth control when he promoted it in his encyclical Humanae Vitae.

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Why is NFP evil? NFP is evil because it is birth control; it is against conception. It is a refusal on the part of those who use it to be open to the children that God planned to send them. It is no different in its purpose than artificial contraception, and therefore it is a moral evil just like artificial contraception. The Teaching of the Catholic Papal Magisterium Pope Pius XI spoke from the Chair of Peter in his 1931 encyclical Casti Connubii on Christian marriage. His teaching shows that all forms of birth prevention are evil. We quote a long excerpt from his encyclical which sums up the issue.

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One can see that Pope Pius XI condemns all forms of contraception as mortally sinful, because they frustrate the marriage act. Does this condemn NFP? Yes it does, but the defenders of Natural Family Planning say “no.” They argue that in using the rhythm method to avoid conception they are not deliberately frustrating the marriage act or designedly depriving it of its natural power to procreate life, as is done with artificial contraceptives. They argue that NFP is “natural.” (Common sense should tell everyone who deeply considers the topic that these arguments are specious and deceptive, as NFP has as its entire purpose the avoidance of conception). However, the attempted justification for NFP – that it doesn’t interfere with the marriage act itself and is therefore okay – needs to be specifically refuted. And it is specifically refuted by a careful look at the teaching of the Catholic Church on marriage and ITS PRIMARY PURPOSE. It is the teaching of the Catholic Church on the primary purpose of marriage (and the primary purpose of the marriage act), which condemns NFP. Catholic dogma teaches us that the primary purpose of marriage (and the conjugal act) is the procreation and education of children.

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Besides this primary purpose, there are also secondary purposes for marriage, such as mutual aid, the quieting of concupiscence and the cultivating of mutual love. But these secondary purposes must always remain subordinate to the primary purpose of marriage (the procreation and education of children). This is the key point to remember in the discussion on NFP.

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Therefore, even though NFP does not directly interfere with the marriage act itself, as its defenders love to stress, it makes no difference. NFP is condemned because it subordinates the primary end (or purpose) of marriage and the marriage act (the procreation and education of children) to the secondary ends. NFP subordinates the primary end of marriage to other things, by deliberately attempting to avoid children (i.e., to avoid the primary end) while having marital relations. NFP therefore inverts the order established by God Himself. It does the very thing that Pope Pius XI solemnly teaches may not lawfully be done. And this point crushes all of the arguments made by those who defend NFP; because all of the arguments made by those who defend NFP focus on the marriage act itself, while they blindly ignore the fact that it makes no difference if a couple does not interfere with the act itself if they subordinate and thwart the primary PURPOSE of marriage. To summarize, therefore, the only difference between artificial contraception and NFP is that artificial contraception frustrates the power of the marriage act itself, while NFP frustrates its primary purpose (by subordinating the procreation of children to other things).