When it comes to the work of Christian unity, actions speak louder than words. Gestures such as Paul VI handing his episcopal ring to Archbishop Michael Ramsey or John Paul II and Archbishop Robert Runcie praying together in Canterbury Cathedral have made as big an impact as any number of joint statements. Pope Francis and the current Archbishop of Canterbury are making their own efforts to show that Christians should, as Francis has put it, act “as if they are already united”. Justin Welby was in the Vatican to meet the Pope last week. It was his fourth private audience, and, unusually, it was followed by an invitation to stay for lunch.