The 54-year-old actor is carrying a heavy cross. If anything is holding him together, he says, it’s his faith in God, whom he thanks for miraculously funding the film and for guiding him through the Hollywood swamp toward the Kingdom. In “Sound of Freedom,” his lonely journey is underlined by an eerie absence of extras and wide zoom shots of him working in a deserted federal office. In thousands of dark, chilly theaters across the country, a fervent Catholic movie star , famous for his grisly portrayal of Jesus, is playing a Mormon missionary perhaps best known for pretending to...