Many atheists have alleged that great harm has been done by religion, christianity in particular. Even if they have overstated their case, we can, and must, still learn from their criticisms. And if the analysis is fair, we have all the more reason to listen and repent.
Keith Parsons is a US philosopher and atheist who writes about the philosophy of religion, and actively engages with christian belief via The Internet Infidels website and the Secular Outpost blog. Keith has made his assessments of christianity in two posts on Secular Outpost, and they are worth checking out.