Unapologetic is a brief, personal, sharp-tongued defence of Christian belief. It isn't an argument that Christianity is true, because how could anyone know that (or indeed its opposite)? It's a book for believers who are fed up with being patronised, for non-believers curious about faith in the twenty-first century, and for anyone who feels there is something indefinably anti-imaginative and intolerant about the way the atheist case is currently being made.
