For too long, serious churches have ceded ground to the left on cultural issues that the left integrated into politics, and they’re running out of time to act. I was fortunate enough to see an early screening of a brand-new film based on Eric Metaxas’ best-selling book, Letter to the American Church. The hour-long film, which shares the book’s name, vividly lays out the case that it is high time Christians in this country got seriously involved in the cultural and political arena. The author’s narration is accompanied by rapid-fire images that help convey the urgency of the days in...