On Wednesday, Francis left little doubt about his view.
"If we look at the history of the church, we will see that every time the bishops have not managed a problem as pastors, they have taken a political stance on a political problem," he told reporters on his plane as he returned from a four-day trip to Hungary and Slovakia. He cited a history of atrocities committed in the name of the faith when the church became involved in politics.
"What must the pastor do?" he asked. "Be a pastor, don't go condemning. Be a pastor, because he is a pastor also for the excommunicated."
The issue has become one of the deepest rifts within the church in the United States, as well as between the US church and the Vatican. With an observant, liberal Catholic in the White House, some leading US prelates want to draw a harder line on abortion, making opposition to it a more central requirement of the faith.
Bishop Michael F. Olson of the Diocese of Fort Worth, Texas, described Biden's support for abortion rights, even as he portrays himself as a faithful Catholic, as "gravely scandalous," and said it led to confusion about church teaching.
Olson, who is on the committee of US bishops drafting new guidelines for administering the Eucharist, insisted that the pope's comments should not be interpreted as a rebuke to US prelates.
"We're not at odds with the Holy Father and he's not at odds with us," Olson said. "He wants us to be pastors, and we also want to be pastors. But a pastor is not just a mascot for one's private point of view."
A spokeswoman for the U.S. Conference of Catholic Bishops, Chieko Noguchi, declined to comment on the pope's remarks.
Though Francis' comments have no official implications for the US bishops' stance on Communion, they illustrate a widening gap.
"This will be one other brick in the big wall built since 2013 between this pontificate and the majority of these bishops," said Massimo Faggioli, a professor of theology at Villanova University in Pennsylvania and author of a book about Biden's Catholicism. "That's a major historical change."
Francis told reporters traveling with him that "Communion is not a prize for the perfect," echoing statements he has made in the past, if not specifically in the context of politics or the United States. At a Mass in June, arguing that the church must be as open as possible, he said, "The Eucharist is not the reward of saints but the bread of sinners."
On Wednesday, the pope emphatically restated the Catholic position that abortion is homicide. "Abortion is more than a problem — abortion is homicide," he said, speaking in Italian. "Whoever has an abortion kills."
"It is a human life," Francis said. "This human life must be respected — this principle is so clear."
Despite warnings from Rome, the US bishops conference voted in June to draw up the Eucharist guidelines, which conservatives hope can be the basis for refusing Communion to politicians who back abortion rights. The proposed guidelines are expected to be put to a vote of the bishops in November, with two-thirds approval needed for adoption.
The pope's comments came as abortion has once again moved front and center in the politics of both the United States and Mexico.
This month, the nation's most restrictive abortion law went into effect in Texas, and the Biden administration has gone to court to try to block it. And the Supreme Court is scheduled to take up a Mississippi abortion law in a case that anti-abortion campaigners hope will overturn the abortion rights precedents set by Roe v. Wade in 1973 and subsequent rulings.
Mexico's Supreme Court last week handed down a ruling that decriminalised abortion in the country.
Francis was not asked about, and did not address, the US or Mexican legal cases.
The pope also touched on other issues, among them the rise of antisemitism — it "is making a resurgence, it is fashionable, it is an ugly, ugly thing," he said — and his brief encounter Sunday with Prime Minister Viktor Orban of Hungary. He said the Hungarian leader's anti-immigrant policies had not come up.
Asked about the European Parliament's resolution this month that calls on member states to recognize same-sex marriages contracted in the European countries where such unions are possible, Francis reiterated that marriage was a sacrament and that there were civil laws to "help the situations of many people who have a different sexual orientation."
The pope, who has taken a notably tolerant stand on gay people compared with his predecessors, spoke of civil unions as a way to meet people's needs. But he said that "marriage is marriage" between "a man and a woman."
People of different sexual orientations can participate in church life, he said, "but please, don't make the church deny its truth."
Francis also reiterated the importance of being vaccinated against the coronavirus when asked about Christians in Slovakia being divided over inoculation. He made an apparent reference to a US cardinal, Raymond Burke, who spread vaccine misinformation and then was treated for Covid-19 at the Mayo Clinic in Rochester, Minnesota.
"Even in the College of Cardinals," Francis said, "there are some anti-vaxxers, and one of them, poor man, is in hospital with the virus. But life is ironic."
This article originally appeared in The New York Times.
Written by: Elisabetta Povoledo, Richard Pérez-Peña and Ruth Graham
© 2021 THE NEW YORK TIMES