A “flop.” That’s how Australian web site TheMusic.com.au disparaged “Let Hope Rise,” the concert documentary featuring Hillsong United, which debuted three weeks ago here in the United States. As of this past Friday, the film has earned $2.3 million. That’s little more than a tenth the sum earned over the same span by, say, “Blair Witch,” as Hillsong’s detractors would no doubt point out. But the success of “Let Hope Rise” cannot be measured by the standards of Mammon, the god worshiped by the secular world, but by the Great Commission the risen Christ issued to his followers: “Go into...