"to go beyond words and experience the living moment non-discursively with a clarity of apprehensive immediacy in which the subject - object dichotomy may dissolve.
Such experiences may be accompanied by moments of profound inner stillness, a rising sense of physical and mental bliss, and an awareness seemingly unlimited by previous imputations of self-regarding thought."
OK so that's writing about what could be called a Zen state of being, an enlightened or awakened state of mind, to use two almost useless decriptions. Some might be put off by John Crook's abstract language, but I think it's actually very helpful. "the living moment non-discursively" i.e. presentmomentness, in my crude shorthand, released from verbal concepts.
"Subject-object dichotomy may dissolve," i.e. usually I (you too) live feeling there is me, and there is the world about me, a subject and an object. In the Zen state, there is a feeling of profound unity with - everything. This state of unity is the subject of writings by "religious" people e.g. Christian mystics, and TS Eliot:
At the still point of the turning world. Neither flesh nor fleshless;
Neither from nor towards; at the still point, there the dance is,
But neither arrest nor movement. And do not call it fixity,
Where past and future are gathered. Neither movement from nor towards,
Neither ascent nor decline. Except for the point, the still point,
There would be no dance, and there is only the dance.
I can only say, there we have been: but I cannot say where.
And I cannot say, how long, for that is to place it in time.
"Burnt Norton," The Four Quartets
Writers often use paradox to suggest the break-out from dualistic thinking they are trying to get across; Zen is famously full of paradox, e.g. koans that make no logical sense - which is exactly their value.
"Spiritual" is so over-used that it's not very helpful, but some people might call such perceptions as Crook's and Eliot's "spiritual" rather than necessarily "religious." To approach this state of being, you don't have to belong to any church; you don't have to believe in supernatural beings or a life after death to understand, to accept this reality.
Or of course you could simply stop worrying about such dichotomies, such dualistic thinking - religious/nonreligious, enough already, let's just get on with it!
This extraordinarily acute awareness may be associated with feelings of profound gratitude, openness to others and compassion. Only a few experience this state in depth, but many discover a radically quietened mind in which self-acceptance leads to a loss of personal anguish, together with the emergence of a new view of life in which openness and optimism are characteristic. There is in particular a remarkable feeling of having shed a burden, and a consequent feeling of freed energy.
And here's John Crook, who set up Maenllwyd retreat centre many years ago, writing about certain kinds of retreat:
The prime initial feature of a successful retreat is simply self acceptance: the retreatant has discovered that being alive as ‘me’ is not so dreadful after all, that there can be mysterious joy in forgetting oneself, letting go into simple bare awareness of the present - whatever it is. We call this ‘self at ease’ and it is an opening to ‘clarity’. Deeper levels of this experience give rise to a sense of oneness with the world or cosmos in which the machinations of self are temporarily forgotten.
Forgetting the machinations of the self for a bit sounds like a good idea to me, probably worth the rigour of a few day's silence.