Republican presidential contender Donald Trump introduced Gov. Mike Pence (R-Ind.) as his running mate on July 16. Here are the key moments from his announcement. (Jenny Starrs/The Washington Post)

Donald Trump’s vice presidential pick, Mike Pence, no longer talks about why he has called himself an “evangelical Catholic” in the past, but the phrase says a lot about religion, Indiana and the governor himself in 2016.

Pence has been described for years as a “devout evangelical,” although he describes himself as “a Christian, a conservative and a Republican, in that order.”

But the faith journey of the man who could potentially be the next vice president isn’t clearly known.

One of the more publicly shared accounts of Pence’s transition from a Catholic youth minister who wanted to be a priest to an evangelical megachurch member came in 1994. That’s when he told the Indianapolis Business Journal about an intense period of religious searching that he underwent in college. “I made a commitment to Christ,” Pence said, speaking of the late 1970s. “I’m a born-again, evangelical Catholic.”

Craig Fehrman, an Indiana freelance journalist who has written about Pence’s faith over the years, said he has questioned the governor and has been met with diminishing specificity. Pence always points to 1978 (his freshman year of college) as the point of his “conversion” to evangelical Christianity, yet after that he still attended Mass, worked as a youth pastor at a Catholic parish, met his wife at Mass and applied to graduate school with the intention of becoming a priest, Fehrman said Friday.

In a 2013 profile of Pence, Fehrman said the then-new governor rebuffed repeated attempts to talk more about how he shifted faith identities. The son and grandson of Baptist clergy, Fehrman was fascinated by the switch of a politician who grew up in a family of Irish Catholic Democrats and asked for more detail.

“All he’d say was ‘I cherish my Catholic upbringing,’ ” Ferhman said. The profile, in the Indianapolis Monthly, quotes Pence as saying “I’m a pretty ordinary Christian.” Pence declined to say where he and his family went to church, saying only, “We’re kind of looking.”

The only clear chronology Ferhman said he sees is that many Pence friends describe the mid-1990s as a “time of maturing” for the governor. In the 1994 piece, Pence calls himself Catholic, and then by 1995, the Indianapolis Star was reporting that Pence was attending an evangelical megachurch.

That was around the time that white evangelicals and conservative Catholics in the United States started to realize they had a lot more in common than their more denominationally tribal parents realized. Pollsters and sociologists note that in the 1990s and early 2000s, conservative white Catholics in particular and white evangelicals began making alliances over shared concerns, primarily traditional marriage, abortion and legal religious protections.

Today, most prominent social conservative advocacy groups are a combination of these forces, whereas a generation or two ago such groups were far more homogeneous.

It’s a common trend among evangelicals today to be interested in ancient practices of the Catholic and Orthodox churches such as confession or communion — seen by some as more classic and traditional.

Pew Research reported last year that while most religious groups lost market share due to Americans’ switching faith identities, evangelical Protestants did not — gaining more converts than they lost as people who had grown up evangelical moved on. And among those converts are Catholics, including prominent politicians such as Pence and Marco Rubio, who left Catholicism for Mormonism and the Southern Baptist Convention before ultimately returning to Catholicism.

The actual number of converts — in both directions — is small. According to Pew, less than 1 percent of adults who were raised evangelical now identify as Catholic, and about 3 percent of adults who were Catholic are now evangelical. But the connection between conservatives in both communities has fortified, resulting in a religious slang where “evangelical-Catholic” kind of means “we are both conservative Christians who share some views and practices.”

Pence’s term infuriates some — particularly more progressive Christians — who say important theological differences are being downplayed for political purposes.

Christopher Hale, who led national Catholic outreach for President Obama’s 2012 campaign, tweeted this as Pence was picked:

Jacob Lupfer, a religion blogger, said the term conflates “two distinctive traditions in the name of political expediency. And though they claim to be concerned about theological rigor, they create considerable confusion…Just because a few Catholics and evangelicals subscribe to the same conservative magazines does not mean there’s such a thing as ‘evangelical Catholicism.'”

Arthur Farnsley II, associate director of the Center for the Study of Religion and American Culture at Indiana University-Purdue University in Indianapolis, said Pence’s state has a good-size Catholic population of people who are aligned theologically with evangelicals.

“They are biblically conservative and probably conservative on traditional values — as he is,” Farnsley said of Pence.

While liberal Catholics might not love the term “evangelical Catholic,” many conservative types “wouldn’t flinch,” he said. “Given the alliances between conservative Catholics and evangelicals on abortion, I don’t think people would be moved.”

Pence, Fehrman says, was “pulled between two worlds.” When he called himself an “evangelical Catholic,” Fehrman says, “I think he wasn’t making a fine theological point, but was torn between his family’s faith and background and a new and more exciting faith.”

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