To Pastor Adam Barkley, his ministry is all about multiplication versus addition.Barkley left Friday on a month-long mission trip to Cuba to train pastors there in building and growing healthy churches."My passion is to see Christians live the successful Christian life, and mature in their relationship with God," Barkley said. "If I train a dozen pastors, then they will go and train their congregation who will plant new churches. It's a ministry of multiplication versus addition."Barkley, 49, became a pastor for First Baptist Church in 2000, leaving the church in 2009 to devote his time to mission work.He has trained …