Until Monday, the go-to event at this weekend’s annual meeting of the Catholic Theological Society of America was titled “Sacramental-Liturgical Theology Since Vatican II: The Dialectic of Meaning and Performance.”

But that was before the nun sex book.

That’s shorthand now for the writings of Sister Margaret Farley, a 70-something theological heavyweight, whose book, “Just Love” was censured by the Vatican this week for its empathy toward same-sex marriage, masturbation and divorce, among other activities totally forbidden by Catholic teaching.

Now the must-attend event for members of the world’s largest group of theologians, is an interview with Farley, the group’s past president and a matriarch of feminist theologians.

Catholic sexual ethics, like everything else in American Catholicism — and perhaps America as a whole these days — is divided into two galaxies.

There’s the Farley-like camp at the Society, with more than 1,300 members, which has generally embraced more open, liberal interpretations of Catholic sexual ethics. They long ago OKed papal no-nos like premarital sex and same-sex relationships, and are more focused now on things like creating stable families led by equal partners and the impact of toy marketing and media on girls’ moral values.

Then there’s masturbation. While banned by the church, Farley wrote, the practice is neither inherently good, or bad.

“Self-pleasuring,” Farley said, can help or harm “well-being or the liberty of spirit” — it depends.

Her thinking was in keeping with that of many of her liberal colleagues.

“Younger Catholic scholars are seeing a big divorce rate, a hook-up culture. (But) they aren’t on the bandwagon of condemning. They just want to give people more sense of direction,” said Lisa Sowle Cahill, a Boston College theologian who is interviewing Farley for the Friday night talk.

Cahill added, rather sarcastically: “But some people would rather talk about masturbation, which is so much more important.”

More conservative thinkers join the much-smaller Academy of Catholic Theology or Fellowship of Catholic Scholars.

“I don’t belong and I don’t know of conservative theologians who do. We are definitely not welcome there,” Janet Smith, a prominent moral theologian at the Sacred Heart Major Seminary in Detroit, said of the St. Louis event.

Conservatives theologians argue that Catholic sexual ethics should not change with the times. Ethical behavior must also be judged differently in a sexual relationship than in other relationships, they say. The relationship must be between a man and a woman who are married, who don’t use contraception and who view sex as a means for procreation.

The good of sexuality comes from the fact that it bonds two people and is tied to baby-making, said Eduardo Echeverria, a philosophy professor at Sacred Heart seminary who writes about sexual ethics.

Masturbation violates both those things, he said, and can lead to using pornography or helping someone avoid fixing any sexual problems in their marriage.

The fact that it feels good is meaningless, he said. “Adultery can produce pleasure, so can pedophilia. … Human sexuality has a nature, and it’s toward union and the good of the other.”

While the more liberal sexual ethicists, like Farley, see their role as challenging official teaching to evolve with the times, traditionalists say being a Catholic theologian is about “trying to be faithful to what the church teaches … and to explore the content of revelation,” Echeverria said.

Theologians, Echeverria said, are divided deeply — like Catholics in general — over questions of whether Scripture is the real and immutable word of God. What does it mean to be a committed Christian?

What gets people like him, he said, is that the Theological Society-types barely address church teachings or people supportive of church teachings in their arguments.

“It’s as if intelligent people can’t really believe what the church teaches,” Echeverria said. “There are all these (huge theologians in the past) who wanted to be faithful to the mind of the church, and it’s as if, ‘We don’t bother to read these people.”

Farley, who has been challenging church teachings on the male-only priesthood and abortion for decades, is an author favored by liberals. On the right, the celebrity theologian is Christopher West, who used to do marriage preparation classes for the Washington Archdiocese and runs seminars and chats on the radio about Pope John Paul II’s landmark “Theology of the Body.”

Meanwhile, the censure by the Vatican’s Congregation for the Doctrine of the Faith continued Thursday to elevate Farley far beyond theological circles. Her book, which came out in 2006, remained in the top 20 bestsellers on Amazon, above “The Hunger Games” box set but below “Eat to Live.” That’s about 200,000 spots higher than where it sat before the censure was announced.

“Have they seen ‘Footloose’ at the Vatican? Jeez,” said Rocco Palmo, a popular blogger who writes about the Vatican and the U.S. clergy. Meaning: Forbidden fruit tastes better.

In St. Louis, the Theological Society’s board on Thursday approved a statement in support of Farley, who has been comfortable in the center of controversial sexual and gender storms for decades.

The board is “especially concerned,” its statement read, about the Vatican’s view of the role of theology.

The notification by the Congregation for the Doctrine of the Faith “risks giving the impression that there can be no constructive role in the life of the Church for works of theology that 1) give voice to the experience and concerns of ordinary believers, 2) raise questions about the persuasiveness of certain official Catholic positions, and 3) offer alternative theological frameworks as potentially helpful contributions to the authentic development of doctrine.”

While many won’t be in St. Louis this weekend, conservative sexual ethicists have had their own flurry of activity since the announcement of the notification, the first from the Vatican’s Congregation for the Doctrine of the Faith in five years.

Colorado theologian E. Christian Brugger wrote a piece entitled “Three Cheers for the CDF.” Others zapped around critical reviews from when Farley’s book debuted in 2006. This week moral theologian William E. May called Farley’s work “atrocious” and said she is arrogant.

“People have gone into their own enclaves,” Cahill said.