The questions that swirl at the center of The Amen Corner — about faith, sin, redemption, and hope — haven't changed since James Baldwin wrote the piece 60 years ago, and they aren't likely to shift anytime in the future. In Penumbra's production, the moments that focus on these issues — especially among the torn family members at the play's center — are by far the best. Buoyed by a terrific trio of performances, the troubles and dreams of Sister Margaret, estranged husband Luke, and their son David carry the evening with a searing honesty that never plays favorites. Unfortunately, the other elements don't work nearly as well, as the main plot — about Sister Margaret's fall from grace with the Harlem congregation she leads — lacks the subtle touch that marks the rest of the play. Some of the problem is scale. Presented on the Guthrie's Wurtele Thrust, the action threatens to be dwarfed by Vicki Smith's otherwise excellent set and the outsized performances in many of the secondary roles. Then again, no matter the issues, Greta Oglesby is a sight to behold as Sister Margaret, as she tries to stay strong for her church and son as her life crumbles around her. Hannibal Lokumbe presents a different type of intensity as Luke, the jazz-playing trumpeter Margaret left years before. Eric Berryman is the final piece of the three-way dance, bringing out all the hope of a younger generation, both of this postwar setting and of youth generally. Bottle these performances and you have one of the best shows of the year. Taken as a whole, The Amen Corner is a flawed show worth considering.