After reading through some of your responses I have to conclude that the tile you meant to give this thread is Spiritual truth is not constant. You don't seem to have a problem acknowledging that there are physical truths which are constant, like 2 + 2 = 4 or that the Earth orbits around the sun.
We have a reliable method for determining physical truths... it's called the scientific method. Is there a similar reliable method for determining spiritual truths? Personally I don't see how there could be, if as you claim the truths about spirituality aren't consistent. In fact, that suggests that there is no such thing as a spiritual truth, since that 'truth' can be completely different for two individuals and in fact can change tomorrow for any given individual.
Thus, without any reliable method for determining the truth about spiritual claims there are no genuine spiritual 'truths', only spiritual claims that can never be verified.