Most of our witnessing is likely to happen in passing moments of conversation--those occasions when we show, in relatively minor ways, who we are and to whom we belong. I think of a suburban woman who was playing tennis with her good but quite secular friends. In a conversation break between sets she began referring to something she had read that morning. It would have been easy to say, "I read something this morning ." Instead, with no attempt at piosity, she simply introduced one word: "In my devotional reading this morning." It was not a …