Though to say that spirituality is psychological may sound reductionist, that there is nothing true 'beyond' the psychological experience, this need not be the case. It simply means that so-called spiritual experiences are rooted in and have their origin in the human. In this sense, yes, it does purposely exclude 'bolts from heaven'; nothing 'out there' acts on the psychological 'in here' so as to effect a change or grant an experience. This does not deny that there is an absolute Reality (how could it be otherwise?), but only that its possible apperception has its locus solely in the human.
I would add a further caveat, however, and say that whatever experience one might have, it would be mistaken to declare it to be of Absolute Reality. To speak of it is to think it, and to think it is to objectify and contain it, something of which the human mind is incapable. The 'enlightened' Zen master would scoff at my ignorance in this regard, no doubt. Yet, I would suggest that it makes no difference; his enlightenment took place solely within himself, and whether he chooses to declare it absolutely the Absolute or not is immaterial. He may very well have experienced Absolute Reality, but to knowingly pronounce it so is another thing altogether. And why, exactly, would he feel it necessary to do so? Think on this, if you will.
Further, though largely compatible with religious philosophies of Eastern persuasion, this statement does deny the fundamental belief of the theistic Abrahamic religions, namely that there is a God actively involved in our lives and it is He that does, in fact, send transformative bolts from heaven. Though I wish to be inclusive, I see no way to avoid this exclusion. Yet, that exclusion is only provisional; though it seems necessary to choose between them for the purposes of one's own spiritual path, it is not necessary to pronounce either perspective objectively true or false. Moreover, it most certainly does not deny the psychological validity of the theist's experience. Understanding spirituality as psychological allows for an appreciation of every such experience as valid, no matter how attained and by whatever beliefs one has utilized to obtain them.
Although all this might sound like a load of theoretical blabber, it is not so for me. Indeed, isn't this the very crux of both philosophical Daoism's and Zen's insistence that the spiritual breakthrough into transcendence is had in the abandonment of the objective and external? God, Buddha, Mind, Absolute Reality — all these are objective distractions which hinder us from realizing what is beyond all conception. Can you feel that barrier, that thin membrane between the bounded and the unbounded, the limited and the unlimited?
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