As I sat on a train headed for an important appointment, I began to wonder if I was on the right train. I had never traveled that route before and had failed to ask for help. Finally, overcome by uncertainty and doubt, I exited at the next station—only to be told I had indeed been on the right train!

That incident reminded me how doubt can rob us of peace and confidence. At one time I had struggled with the assurance of my salvation, but God helped me deal with my doubt. Later, after sharing the story of my conversion and…