All religious error is dangerous, and ought to be carefully guarded against. "There is a natural connection between truth and holiness, and between error and sin." While the devil 'abode in the truth ' he was holy; and no sooner was man deceived than he became a sinner. Every duty is acting out a truth, and every sin is the embodiment of a falsehood. Is it reasonable to expect that a man will walk in the right way if he does not know it? And, if he is deceived as to this point, what can be anticipated but that he will stray into forbidden paths? Error is not, cannot be, either innocent or safe. It cannot be cherished without both sin and danger.

~ John Brown of Edinburgh
exposition of Galatians 6:7-8