A frequently and (often) intentionally left behind doctrine is the doctrine of hell. And while it shouldn’t be our favorite discussion piece, it may be one of the most crucial to resurface. Where it lands upon hearts, there you will often discover the line between authentic Christianity and truly born again people, and, by contrast, those who belong to the cultural Christian movement, who bear the name so long as everything is nice and the content of their lives remains unchallenged by biblical authority. Keller discusses the “importance of hell” here.