This week Mary Stallard talks to US speaker and author Rob Bell, who's on tour in the UK this week. He's a former mega-church pastor from Michigan who founded one of the most influential evangelical churches of the 2000s. His books and videos outlining a fresh approach to Christian faith and the need for change are read and watched the world over, but the publication of his best-selling book Love Wins in 2011 proved to be hugely controversial. He left his role as a pastor and today he's in demand internationally as a speaker, teacher, and writer. He's just published a new book, What is the Bible, and his Holy Shift tour is in Cardiff this week.