On Sundays, I used to stand in front of my Mormon congregation and declare that it all was true.

I’d climb the stairs to the pulpit and smooth my long skirt. I’d smile and share my “testimony,” as the church calls it. I’d say I knew God, Jesus Christ, the Holy Ghost, prayer, spirits and miracles were all real. I’d express gratitude for my family and for my ancestors who had left lives in Britain, the Netherlands, New Zealand and Norway to pull wagons across America and build a Zion on the plains. When I had finished, I’d bask in the affirmation of the congregation’s “amen.”

In that small chapel by a freeway in Arkansas, I knew the potency of believing, really believing, that I had a certain place in the cosmos. That I was eternally loved. That life made sense. Or that it would, one day, for sure.

I had that, and I left it all.

I never really wanted to leave my faith. I wasn’t interested in exile — familial, cultural or spiritual. But my curiosity pulled me away from the Church of Jesus Christ of Latter-day Saints and toward a secular university. There, I tried to be both religious and cool, believing but discerning. I didn’t see any incompatibility between those things. But America’s intense ideological polarity made me feel as if I had to pick.

My story maps onto America’s relationship to religion over the last 30 years. I was born in the mid-1990s, the moment that researchers say the country began a mass exodus from Christianity. Around 40 million Americans have left churches over the last few decades, and about 30 percent of the population now identifies as having no religion. People worked to build rich, fulfilling lives outside of faith.

That’s what I did, too. I spent my 20s worshiping at the altar of work and, in my free time, testing secular ideas for how to live well. I built a community. I volunteered. I cared for my nieces and nephews. I pursued wellness. I paid for workout classes on Sunday mornings, practiced mindfulness, went to therapy, visited saunas and subscribed to meditation apps. I tried book clubs and running clubs. I cobbled together moral instruction from books on philosophy and whatever happened to move me on Instagram. Nothing has felt quite like that chapel in Arkansas.