At a winter retreat in northern New England, one of the men asked the question, “What was your favorite Christmas gift ever?”

One athletic man seemed eager to answer. “That’s easy,” he said, glancing at his friend next to him. “A few years back, I finished college thinking I was a sure bet to play professional football. When it didn’t happen, I was angry. Bitterness ate at me, and I shared that bitterness with anyone who tried to help me.”

“On the second Christmas—and second season without football—I went to a Christmas play at this guy’s church,” he said, gesturing toward his friend. “Not because I wanted Jesus, but just…