A couple times a week, I’ll quietly leave the house to meet with a group of runners – to get some miles in before the sun is up and the kids are awake. Most of the conversations in those early hours are light and bright: we catch up on each other’s families and work, and, shockingly, talk about running. But I have one friend who is not into that kind of conversation. He’s Presbyterian, a strong Christian, active in his church, and he loves asking me tough questions. “Can you tell me what you Catholics really believe about the pope?” “Why do you Catholics reserve the Eucharist at the end of Mass instead of consuming everything?” “Can you tell me…