The seriousness of errant doctrine can be compared to a missile aimed a mere one degree off target. The difference seems slight and negligible at first, yet the results of the error increase dramatically throughout the flight of the missile, until it totally misses its intended target.

So it is with false doctrine. At first it may seem to be a tolerable mistake, a little error—but not that serious. But, as with all errors, the effects compound over time until they become so serious that they may not be correctable.