If the truly spiritually connected person picks up the message that he should drown his children in the bathtub

From a false premise, all things become possible. "Truly spiritually connected" people (speaking in general) learn to discriminate (just as intelligent, non-spiritual people do) between messages that are coherent, relatively rational and which aid broad well-being, and those which emanate from the deep black wells of psychosis. Just because a voice is "spiritual" (a very loose term, here) does not mean it is sane, and knowing the difference is critical to "spiritual" survival (another somewhat oxymoronic proposition, but that's another thread). Ghosts tales and voodoo stories are full of examples of "spiritual" entities in the grips of insanity. One could argue, even, that it takes a certain measure of madness to become a ghost at all, obsessing about the past, revenge, incomplete discussions, and the like.