Miguel Vidal / Reuters

There’s been lots of gay-marriage news in America lately. Yes, the Supreme Court ruled that same-sex marriage is a Constitutional right, but in the religion world, another headline might matter more: On July 1, the Episcopal Church decided to allow same-sex wedding ceremonies. The decision won’t apply to all churches and dioceses—priests can choose not to perform ceremonies if they wish—but it represents an important shift in American religion. Now that gay marriage is a legal right, churches and synagogues and mosques have to consider whether it should be a religious right within their traditions, too.

Some groups have already considered this question. Conservative and reform Jews allow gay marriage; Orthodox Jews do not. Three of the four major Protestant denominations in the U.S. allow it; Catholics, Mormons, and many Baptist and evangelical denominations do not. Islam prohibits it; it’s unclear whether Hinduism and Buddhism do the same, according to Pew.

Now that gay marriage has become a religious and cultural question in the United States, rather than a political or legal one, religious institutions will help determine how “normal” same-sex marriage will become. As of now, it’s a huge life event that can take place in everyone’s political lives, but only some people’s religious lives. If same-sex spouses have to maintain a divided relationship, only fully accepted in certain parts of their lives, will they decide to stop going church or mosque or synagogue altogether? And will heterosexual people who support gay marriage also find themselves alienated from religion, particularly religious groups that have reaffirmed their opposition to gay marriage?

Some of this has probably already happened. Surveys suggest that a growing number of Americans are religiously disaffiliated, meaning they don’t see themselves as part of any particular group. “One of the huge influences in why there was such strong disaffiliation is because Christianity came to mean right-wing, evangelical, judgmental, nasty,” argued Casper ter Kuile, a Harvard Divinity School student, at the Aspen Ideas Festival on Thursday. According to a 2014 survey by the Public Religion Research Institute, ter Kuile is right about how a lot of Americans feel: Nearly 60 percent said religious groups alienate young people by being too judgmental about LGBT issues. Among Millennials, or those aged 18 to 33, the portion was closer to 70 percent.

In general, Millennials are more religiously unaffiliated than any American generation that came before them. There are a lot of complicated reasons for this, and researchers can’t predict what will happen when more members of this generation start getting married and having kids—a time of life when a significant portion of non-practicing people return to religion. But one thing researchers do know about Millennials is that their sexual politics are more progressive than their older adult peers. As of last February, an estimated 70 percent of Millennials said they supported same-sex marriage, compared with less than 40 percent of people 68 and older. Roughly 56 percent said sex between two adults of the same gender is morally acceptable, compared to only 29 percent of those 68 and older. These views vary widely across denominations—evangelicals, for example, are much more likely than their mainline peers to condemn same-sex marriage and gay sex. But even within those groups, there’s a generational gap: Five years ago, Pew found that nearly 40 percent of evangelical Christians aged 18 to 29 thought homosexuality should be accepted by society, compared to less than 25 percent of evangelicals over 30.

At least in the context of Islam, said Jordan Alam, an activist who works on Muslim and LGBT issues, “older folks ... are uncomfortable in talking about sexual politics at all.” She said she knows imams who are willing to perform same-sex marriage or who are openly gay—as in any religion, there is a spectrum of attitudes toward sexuality and LGBT issues. But for the most part, she said, there is a “deep discomfort” with these issues among older adults, who are often the leaders in houses of worship. Insofar as this is true of other religious groups, it may be a factor in whether Millennials decide to embrace religious identity.

Even though the Supreme Court’s decision in Obergefell v. Hodges doesn’t compel religious groups to perform same-sex marriage or change their teachings on homosexuality, it will almost certainly be influential in religious communities. “[Gay marriage] got the conversation to places that we weren’t before,” Alam said.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.