PRESS PHOTOS BY PAUL WILLISTEINThe annual Lehigh Valley Chapter of the American Guild of Organists' “Bach Marathon,” to celebrate the March 21 birth date of Johann Sebastian Bach, was held March 24 in the “Arts at St. John's” series at St. John's Evangelical Lutheran Church, Allentown. Organists performing works by Bach or works influenced by Bach were, from left, Stephen Williams, Luke DiGiacinto