Zika-related exception to contraception ban has implications for other sexual, medical issues.

The Catholic Church prohibits both contraception and abortion. But by putting them on very different moral planes this week, Pope Francis cracked the door to a more-open approach on artificial birth control—and to a greater emphasis on the role of individual conscience. The question of when and how a Catholic may follow his or her own conscience in matters of sexual and medical ethics has implications far beyond contraception.

During his in-flight news conference this past week, the pope broke with his predecessors on the issue of same-sex marriage, saying that Catholic politicians are free to decide how to vote on the matter using a “well-formed conscience.” (He did say, with regard to adoption by same-sex couples: “I think what the church has always said about this.”)

Alarmed conservatives now fear that any relaxation on contraception threatens the church’s broader stance on medical ethics and its belief that sexual relations and reproduction are intrinsically intertwined. That could allow for less-strict positions on assisted-fertility, homosexual sex and divorce. “The Pope’s own words are—at best—confusing,” Philip Lawler, editor of the Catholic Culture website, wrote in a commentary titled: “The damage done—again—by the Pope’s interview.” On his flight home from Mexico on Wednesday, Pope Francis told reporters that contraception could be permissible in areas afflicted with the mosquito-borne Zika virus, because of growing evidence linking it to a serious birth defect. The Rev. Federico Lombardi, the Vatican spokesman, underscored Friday that the pope was speaking of exceptional circumstances. The pope was saying that, in “situations of grave urgency, a well-formed conscience can see if there is the possibility or necessity of recourse” to “contraception or condoms,” he said.

For decades, Catholics have fiercely debated whether is it permissible to use condoms to prevent the transmission of AIDS—something the Vatican has never endorsed.

Pope Francis noted that Pope Paul himself permitted its use by nuns in the former Belgian Congo threatened with rape. Conservatives drew a sharp distinction between rape and voluntary sexual relations. “U.N. officials are now suggesting that artificial contraception should be practiced by married couples routinely because of the Zika epidemic,” Mr. Lawler wrote. “Nothing in the Pope’s statement suggested that there is an inherent moral problem with that approach.” Liberals emphasize the importance of following one’s conscience, as opposed to abstract rules that don’t account for personal circumstances and challenges. Conservatives fear an overly expansive notion of conscience as a euphemism for licentiousness. Many conservatives also regard contraception as a gateway to abortion—an act that is unequivocally banned by the church, as Pope Francis himself reiterated. “Abortion is not the lesser of two evils. It is a crime,” the pope said. “It is to kill someone in order to save another. This is what the Mafia does. It is a crime, an absolute evil.”

Large majorities of Catholics in the U.S. and other countries already reject the prohibition on contraception. According to a poll by the Pew Research Center published last fall, 66% of self-identified American Catholics said they don’t believe it is a sin to use contraceptives. While Pope Francis’ approach has been more nuanced, he has remained firm in his opposition to couples in the rich world using artificial contraception for lifestyle reasons. During one address in Mexico this past week, he mocked a hypothetical couple who put off childbearing to indulge in a pleasant lifestyle. But he has expressed empathy for poor families who may seek to limit the size of their families. He has even encouraged very poor families to do so, using natural methods approved by the church, saying that parents need not “be like rabbits” to be good Catholics.

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