Paul VI’s landmark encyclical on birth control, Humanae Vitae, turns fifty this year. It was controversial before it was written and has remained controversial ever since. Paul’s refusal to permit contraception has, one can say with only mild hyperbole, driven progressive Catholics batty. But for a variety of reasons, both theological and political, the encyclical remains relevant today—not only to Catholics, but to Christians of all stripes.

Christians, especially in the United States, owe much to Paul’s prophetic act. Humanae Vitae is the foundation, in a real sense, of the Church’s uncompromising pro-life position. Certainly, Pius XI and Pius XII had made repeated magisterial statements about abortion, sterilization, and contraception. The value of Humanae Vitae lies in how unexpected it was. The papal commission set up by Paul to study the question of contraception had reported in favor of at least some forms of it, and various reports and drafts of the commission had found their way into the press. There was a widespread expectation that Paul would issue an encyclical approving hormonal contraception. Humanae Vitae, therefore, came as a major surprise.

Since then, the Church’s defense of unborn life has been based on Paul’s refusal to permit any form of contraception. Humanae Vitae shows that permitting contraception would open a door to abortion and sterilization. Paul emphasized that it is no argument to say that contraception might avert some greater evil—it is not, he tells us, licit to do evil that good may result. These themes would be taken up, developed, and expanded by John Paul II over the course of his long pontificate, especially in the 1995 encyclical Evangelium Vitae.

In this sense, Christians have Paul VI and Humanae Vitae to thank for what is, for many, their primary political orientation. Even now, after other fronts have opened up in our battles over sexual morality, the pro-life question remains central for American Christians. In 2016, Christians who expressed concerns about Donald Trump’s qualifications, moral and otherwise, for the presidency were told that Trump would appoint pro-life judges who would begin rolling back the line of cases stretching from Whole Woman’s Health v. Hellerstedt all the way back to Roe. More recently, Roy Moore’s candidacy for U.S. Senate was advanced, in part, with arguments that Moore would be a reliable vote for pro-life judicial nominees. Humanae Vitae laid the foundation for these political imperatives.

Had Paul opened the door to contraception, the modernists and progressives would have pushed the door farther open, using a specious understanding of development of doctrine. This is what happened in the Anglican Communion after the Lambeth Conference of 1930, and one sees signs that it is happening in the Catholic Church today.

The veteran Vatican journalist Edward Pentin has reported conversations he had with Church insiders during the Synod on the Family. According to one insider, undermining Humanae Vitae is the goal of some well-placed progressives in the Church. The argument of Francis’s controversial exhortation Amoris Laetitia is applicable no less to the teaching of Humanae Vitae than to the prohibition on communion for the divorced-and-remarried. One imagines that we will soon see the same “pastoral” logic that permeates Amoris Laetitia and the rhetoric of its supporters used to explain how Humanae Vitae establishes “objective” norms that individuals may or may not be able “subjectively” to live up to. So much for the Council of Trent’s teaching that it is always possible to obey God’s commandments.

Francis’s position on such questions remains to be seen. On the one hand, he has shown little interest in definitively settling the debate over Amoris Laetitia. Even the Buenos Aires guidelines, which he purportedly raised to the rank of authentic magisterium with a note from Pietro Cardinal Parolin, admit of multiple interpretations. It would be unexpected, therefore, if Francis were to declare definitively that there are limits to the reasoning of Amoris Laetitia. On the other hand, Francis has looked to Paul VI’s legacy repeatedly in recent years and cites him often in addresses. It would be very strange if Francis were to undermine directly a central part of Paul’s magisterium. Perhaps Paul himself provides some guidance on this question—and others.

This year also marks the fiftieth anniversary of Paul’s extraordinary Credo of the People of God, which ought to be better known. On February 22, 1967, with the apostolic exhortation Petrum Et Paulum Apostolos, Paul had declared a Year of Faith to mark the nineteenth century since the martyrdom of Sts. Peter and Paul at Rome. The Year of Faith concluded on June 30, 1968, with Paul’s proclamation of the Credo of the People of God. As a gesture, it was unmistakable: The faith is the tradition handed on by the apostles. Before making his profession of faith, Paul offered a few remarks about the Petrine office. The role of the pope, Paul said, was to confirm his brethren in the faith and avoid permitting the desire for novelty to do injury to the faith. In this way, Paul, who may justly be called a pope—if not the pope—of the Second Vatican Council, reaffirmed the great dogmatic definition of the First Vatican Council, Pastor aeternus.

At any rate, I wonder whether Paul had Humanae Vitae, surely then in the final stages of preparation, in mind when he made his profession of faith before the Roman crowd on that June day. Whether he did or not, Humanae Vitae is a shining example—much like John Paul II’s Ordinatio Sacerdotalis—of the Petrine ministry at work. Paul confirmed his brethren in the faith by resisting their desire for development and novelty. It is unfortunate that many Catholics, including some prelates, have failed to see in Paul’s act the hand of Peter.

P.J. Smith writes from southern Indiana.

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Photo by Lothar Wolleh via Creative Commons. Image cropped.