Churchgoing Christians who support "gay marriage" are more likely to approve of commitment-free sexual relations, pornography, adultery, polyamory, and abortion than other churchgoers, says one researcher who calls the differences a "massive divide."

"At a glance, there is a pretty obvious fissure between Christians who do and do not oppose same-sex marriage," University of Texas sociology professor Mark Regnerus wrote in an Aug. 11 essay at the Public Discourse.

"More than seven times as many of the latter think pornography is okay. Three times as many back cohabiting as a good idea, six times as many are okay with no-strings-attached sex, five times as many think adultery could be permissible, thirteen times as many have no issue with polyamorous relationships, and six times as many support abortion rights."

Regnerus suggested that the sexual morality of many churchgoing Christians "shifted years ago" and their acceptance of same-sex marriage "follows significant change rather than prompts it."

At the same time, he suggested that Christian approval of homosexual relationships "has ramifications for how heterosexual relationships are understood, too."

Regnerus drew his data from the "Relationships in America" survey he oversaw as a senior fellow at the University of Texas' Austin Institute for the Study of Family and Culture. The survey interviewed 15,738 Americans aged 18-60 in early 2014 using methods intended to generate nationally representative results.

Regnerus examined the survey responses of self-identified Christians who say they attend church at least three times a month and who reported a position on "gay marriage." He also examined the responses of self-identified gay and lesbian Christians and self-identified gay and lesbian non-Christians.

His analysis focused on respondents' views of sexual morality and abortion rights.

Only five percent of churchgoing Christians opposed to "gay marriage" said commitment-free sex is okay, compared to 33 percent of pro-"gay marriage" churchgoers, 49 percent of gay and lesbian Christians, and 81 percent of gay and lesbian non-Christians.

Regnerus' analysis found great differences on the morality of pornography. About five percent of churchgoing Christians opposed to "gay marriage" said that viewing pornography is okay, compared to 33 percent of churchgoing "gay marriage" supporters, 57 percent of gay and lesbian Christians, and 78 percent of non-Christian gays and lesbians.

Churchgoers who support "gay marriage" were more likely to approve of marital infidelity, with seven percent saying it is sometimes okay, compared to one percent of churchgoers who did not support "gay marriage." About 14 percent of gay and lesbian Christians said marital infidelity is sometimes okay, as did 26 percent of non-Christian gays and lesbians.

Churchgoing Christians who support "gay marriage" were also more likely to support polyamory than were Christians who do not support redefined marriage. Only one percent of Christians opposed to "gay marriage" supported polyamory, compared to 16 percent of those who support "gay marriage," 32 percent of gay and lesbian Christians, and 58 percent of non-Christian gay and lesbians.

While polyamory has long been a fringe phenomenon, it has gained some prominent supporters. President Barack Obama's 2009 nominee for the Equal Employment Opportunity Commission, former Georgetown University Law Center professor Chai Feldblum, disavowed her previously stated support for the 2006 manifesto "Beyond Same-sex Marriage," which included support for households with "more than one conjugal partner."

Christians opposed to "gay marriage" showed greater support for the idea that married couples with children should stay together.

They also showed the strongest opposition to abortion, with only six percent voicing a pro-abortion rights position. By comparison, 39 percent of Christian "gay marriage" backers supported abortion rights, as did 58 percent of gay and lesbian Christians and 72 percent of non-Christian gays and lesbians.

Regnerus denied that his analysis supports a "slippery slope" argument, in which accepting one change in attitude must prompt changes in other areas. Rather, he suggested, Americans are engaged in "social learning" from people they see as "a standard of comparison for ourselves."

Churchgoers opposed to "gay marriage" feel out-of-step from the rest of the nation, while Christians who support it may still "sense that their own views on sexuality still lag behind those gay and lesbian Christians from whom they've have become convinced of the legitimacy of same-sex marriage," he said.

For their part, Regnerus said, gay and lesbian Christians are "not as permissive" as those who are non-Christians, but are "still well above the national average in permissiveness."