WHEN ushered into the master bedroom of the Mormon patriarch Brigham Young at his winter home in St. George, Utah, a few years ago, I felt duty-bound to ask an obvious question: Where did the other women sleep?

Other women? The church tour guide blushed, and laser-stared me as if I’d blasphemed the Mormon Moses. I wondered about arrangements and jealousies, the conjugal timing of a man who was married to 55 women, by most accounts. I didn’t ask about the sexual acrobatics of the great pioneer, just the spreadsheet logistics of managing all those spouses.

All religions undergo historical face lifts. The Church of Jesus Christ of Latter-day Saints, as one of the few faiths subject to modern fact-checking, has had a particularly hard time reconciling its radical founding principles with its white-bread contemporary image. Imagine Mitt Romney with a harem, and you have some idea of the kind of men who planted a new church in the West.

So, it’s been fascinating to watch the reaction to the acknowledgment last month by Mormon leaders that Joseph Smith, the church’s founder and prophet, took as many as 40 wives. Some of the women were also married to other men. One of his brides was a 14-year-old girl, or as church officials put it in an essay, she was “sealed” to Smith “several months before her 15th birthday.” Well, that changes everything.