Pope Francis (real name: Jorge Mario Bergoglio) has shaken up the Catholic church with some plain speaking about faith and about life in the 21st century. He has had an impact on other faiths, as well. Welcome to “pope envy.” I first encountered the term in an essay by Jana Riess, a liberal Mormon writer. “I’ve delighted in seeing this beautiful revitalization of hope in the Catholic Church,” Riess wrote, “but I’ve also felt twinges of (an admittedly un-Christian) envy.” Why wouldn’t a Mormon, or anyone for that matter, envy the un-self-conscious spiritual leadership of a prelate who warns nuns...