VATICAN CITY — During a major summit of the Roman Catholic hierarchy that will end this weekend, a senior conservative bishop took the floor inside the Vatican’s assembly hall and promptly charged his liberal peers with doing the devil’s work.

The three-week gathering, known as a synod, has erupted into a theological slugfest over Pope Francis’ vision of a more-inclusive church, and it has displayed the most bitter and public infighting since the heady days of Catholic reform in the 1960s.

Archbishop Tomash Peta of Kazakhstan captured the magnitude of the divide, raising eyebrows – and a few incredulous laughs – as he decried some of the policy changes floated at the meeting as having the scent of “infernal smoke.”

It was just another day at a gathering that – more than any event since Francis began his papacy in 2013 – has highlighted how the pontiff’s outreach to once-scorned Catholics has triggered a tug of war for the soul of the Catholic Church. More important, it underscored just how hard it may be for the pope to recast the church in his image.

The pushback by traditionalists has been so strong that the chances of fast changes on contentious family issues – whether to offer Communion to divorced and remarried Catholics or to craft more-welcoming language for gays and lesbians – have substantially dimmed, if not died.

As the synod’s end nears, there has been a last-ditch push to find common ground that could at least open the door to policy alterations. But some observers already are comparing Francis to President Obama – a man whose reformist agenda was bogged down by a conservative Congress.

“Francis has the same problem that Obama had,” said the Rev. Thomas J. Reese, a senior analyst for the National Catholic Reporter. “He promised the world, but Congress wouldn’t let him deliver. If nothing much comes of this synod, I think people will give the pope a pass and blame the bishops for stopping change.”

For Francis, the synod – the Vatican’s second in a year on issues related to the family – sets up perhaps the most important decision of his papacy.

The 270 senior church officials, from 122 countries, are scheduled to finish voting on a final document by Saturday. But Francis has the last say, with the power to accept the synod’s recommendations, go beyond them or withhold judgment to encourage further debate.All of those avenues, though, carry risk.

Using his powers to go beyond the synod’s recommendations could rouse the wrath of conservatives, some of whom already are openly questioning the trajectory of his papacy. But if the final recommendation of the synod falls short of liberals’ hopes, rubber-stamping it or encouraging more debate could generate disappointment among Francis’ fans worldwide.

The plot thickened Thursday as an article appeared on a conservative Catholic Web site claiming to be from “a very wise, knowledgeable and highly influential cleric.” It is titled “The Failed Francis Pontificate.”

In it, the author – writing under the pen name Don Pio Pace and using insider terminology – argues that the divided church is now “intrinsically ungovernable” and decries this “strange synod” for being overwhelmingly focused on “adulterous couples and homosexual couples.”

Some also have denounced the general sense of chauvinism hanging over the debates, in which only male clerics have voting rights.

Maureen Kelleher, an American nun serving in one of the non-voting roles at the synod, told the National Catholic Reporter that there were “times that I have felt the condescension so heavy, you could cut it with a knife.”

Speaking of women in general, she added: “I see a high level of non-acceptance of us as holding up half the sky.”