Francis Schaeffer, on the central problem facing the church in every age:

The central problem of our age is not liberalism or modernism, nor the old Roman Catholicism or the new Roman Catholicism, nor the threat of communism, nor even the threat of rationalism and the monolithic consensus that surrounds us. All these are dangerous but not the primary threat. The real problem is this: the church of the Lord Jesus Christ, individually or corporately, tending to do the Lord’s work in the power of the flesh rather than of the Spirit. The central problem is always in the midst of the people of God, not in the circumstances surrounding them.

Obviously, Schaeffer’s list of “-isms” appears rather dated to our eyes, but that only serves to throw his point into sharper relief: the external threats are never as important as the manner in which the church responds to them. Alan Jacobs made a similar point on his blog a while back: “In any given community, there will be a profound divide between those who believe that the most dangerous lies are the ones told by our enemies and those who believe that the most dangerous lies are the ones we tell ourselves.” I believe that (in many cases) you can tell fairly quickly if a person would agree with Schaeffer (and Jacobs) on this question—or not. The implications are far-reaching indeed.