Question: Someone was asking if the moral acceptability of NFP was infallibly taught by the Church and I wanted to refer them to the argument you laid out regarding that very question. I believe it was in “Sex and the Marriage Covenant”, but I lent my copy out so I can’t check. Is it in that book?
John: In my book I did two things in this regard. 1) I reviewed two separate arguments for the infallibility of the doctrine of marital non-contraception and 2) showed that the teaching of that doctrine more than fulfilled the requirements laid down in Lumen Gentium 25 for a doctrine to which the faithful must give religious submission of mind and will.
You are certainly correct in remembering that I dealt extensively with the issue of the infallibility of the teaching affirmed by Humanae Vitae. However, I don’t know exactly what is meant by the wording “the moral acceptability of NFP was infallibly taught by the Church.” I don’t think that acceptability has ever been seriously challenged since 1930 when it first became a practical possibility. Moreover, in 1850 and again in 1880 the Vatican Curial office dealing with matter of the Sacrament of Penance ruled that it was not immoral for a married couple to restrict their marriage acts to [what they think are] the infertile times. The speculation about an infertile time in humans was prompted by its mid-19th century discovery in lower animals, and that speculation imagined that menstruation was the fertile time. Why didn’t the speculators read Leviticus that has couples abstaining during menses? The important thing is that from the first time that the idea of periodic abstinence during the fertile time was raised and until now, the Church has never condemned that sort of periodic abstinence. Recently, it has, of course, had to qualify its acceptance of systematic NFP with the proviso that couples need to have a sufficiently serious reason or “just” reason to use it to avoid pregnancy. Sufficiently serious as contrasted with selfish or frivolous.
I hope this is helpful. Interested parties should read the book. Thanks again for writing.
John F. Kippley
Sex and the Marriage Covenant