What a brave thing to do. Heather McDonald's two-hour monologue about one man's journey to — and away from — God was not kindly received when Kevin Bacon starred in the piece on Broadway. Apparently fast-lane New Yorkers didn't have time to focus on the story of Samuel Gentle, a former pastor whose faith has been challenged beyond understanding. But Mustard Seed Theatre didn't let someone else's failure slow them down. They forged ahead with their own staging, which in the person of Gary Wayne Barker became an evening of gentle civility and uncommon intelligence. Even in a story about alienation, Barker reminded us that an actor alone onstage can become a kind of supplicant in service to both the role and the text.