Carla Pratt Keyes, Pastor of Ginter Park Presbyterian Church in Richmond, Virginia, preaches a sermon called “Awake to Grace,” based mostly on the Old Testament lesson from 2 Samuel 7:1-11, 16. “A few years ago,” she begins, “the youth of my congregation spent their Sunday School hour sitting in the dark. It wasn’t a power outage or some kind of punishment. One of their teachers – who’s a professional photographer – had transformed one of our church offices into a camera obscura…”