Cease practice based
On intellectual understanding,
Pursuing words and
Following after speech.
Learn the backward
Step that turns
Your light inward
To illuminate within.
Body and mind of themselves
Will drop away
And your original face will be manifest.

~ Dogen

The realized man is awake in the light of the Self, while the ignorant is awake in the light of the senses. The realized man is awake in the light of absolute bliss, the ignorant in the light of relative joys of a perishable nature.

~ Maharishi Mahesh Yogi
[Commentary on Bhagavad Gita, Ch2, V69]

Life is this simple: we are living in a world that is absolutely transparent and the divine is shining through it all the time. This is not just a nice story or a fable, it is true.

~ Thomas Merton

The whole truth of life is that there is nothing substantial to bind the never-changing to the ever-changing sphere of life.

~ Maharishi Mahesh Yogi
[Commentary on Bhagavad Gita, Ch2, V15]

As the same sun appears as different when shining on different media, such as water and oil, so the same omnipresent Being, shining through different nervous systems, appears as different and forms the spirit, the subjective aspect of man's personality. When the nervous system is pure, Being reflects more and the spirit is more powerful, the mind more effective. When the nervous system is at its purest, then the Being reflects in all its fullness, and the inner individuality of the spirit gains the level of unlimited eternal Being. Thus it is clear that in its essential nature the spirit is undying and omnipresent. This explains the universality of individuality.

~ Maharishi Mahesh Yogi
[Commentary on Bhagavad Gita, Ch2, V17]

Mostly as a result of meditation, but sometimes during an unexpected glimpse, a mystical experience of an unusual kind may develop.  He feels transparent to the Overself; its light passes into and through him.  He then finds that his ordinary condition was as if a thick wall surrounded him, devoid of windows and topped by a thick roof, a condition of imprisonment in limitation and ordinariness.  But now the walls turn to glass their density is miraculously gone, he is not only open to the light streaming in but lets it pass on, irradiating the world around.

~ Paul Brunton 
[Notebooks Category 22: Inspiration and the Overself; Chapter 6: Experiencing a Glimpse; # 166]