Having a firm grasp and ability to apply a wise principle in one situation does not make one wise in all situations, or even in all situations of a similar nature (in this case, about finances). I think, as Christians, we can often miss this. (Non-Christians also have their versions of this.) There can be a tendency to think that a timeless biblical principle is applicable to every situation within its subject matter. With this belief, we confidently make a biblical assertion and can’t hear reasons against it.