When committed Christians want to talk about their doubts with me, I tell them this first: doubt is not always bad. In fact, sometimes doubt is absolutely essential. Doubt is like pain: it tells us that something nearby us or within us is dangerous. It calls for attention and action. Doubt is not always a virtue, however. There is a dark doubt, an exaggerated and self-destructive doubt that leads to despair, depression, and spiritual self-sabotage. Imagination, for example, is good in itself, but out of control it becomes schizophrenia. Fear is healthy, but out of control fear become paranoia. Sensitivity is a wonderful gift, and anger is a necessary emotion—but either one out of control can lead to depression. Doubt is the same way. Out of control it becomes unbelief, a hard heart, an arrogant or defeatist cynicism. But healthy doubt can serve as a Geiger counter that detects error. Without it we’d be gullible, naïve, and just plain stupid (not exactly stellar spiritual qualities). Doubt is similar to guilt, which the late Christian philosopher Francis Schaeffer said was like a watchdog: useful to have around to alert you to danger. But if the watchdog turns and attacks the homeowner, it needs to be restrained and retrained.

source: Brian McLaren, “Doubt”, in Adventures in Missing the Point: How The Culture-Controlled Church Neutered The Gospel by Brian McLaren & Tony Campolo, 220 tags: Doubt