These are the three stages of enlightenment, the three glimpses of satori.

1. The first stage enlightenment:
A Glimpse of the Whole

The first stage of enlightenment is short glimpse from faraway of the whole. It is a short glimpse of being.
The first stage of enlightenment is when, for the first time, for a single moment the mind is not functioning. The ordinary ego is still present at the first stage of enlightenment, but you experience for a short while that there is something beyond the ego.
There is a gap, a silence and emptiness, where there is not thought between you and existence.
You and existence meet and merge for a moment.
And for the first time the seed, the thirst and longing, for enlightenment, the meeting between you and existence, will grow in your heart.

2. The second stage of enlightenment:
Silence, Relaxation, Togetherness, Inner Being

The second stage of enlightenment is a new order, a harmony, from within, which comes from the inner being. It is the quality of freedom.
The inner chaos has disappeared and a new silence, relaxation and togetherness has arisen.
Your own wisdom from within has arisen.
A subtle ego is still present in the second stage of enlightenment.
The Hindus has three names for the ego:
1. Ahamkar, which is the ordinary ego.
2. Asmita, which is the quality of Am-ness, of no ego. It is a very silent ego, not aggreessive, but it is still a subtle ego.
3. Atma, the third word is Atma, when the Am-ness is also lost. This is what Buddha callas no-self, pure being.
In the second stage of enlightenment you become capable of being in the inner being, in the gap, in the meditative quality within, in the silence and emptiness.
For hours, for days, you can remain in the gap, in utter aloneness, in God.
Still you need effort to remain in the gap, and if you drop the effort, the gap will disappear.
Love, meditation and prayer becomes the way to increase the effort in the search for God.
Then the second stage becomes a more conscious effort. Now you know the way, you now the direction.

3. The third stage of enlightenment:
Ocean, Wholeness, No-self, Pure being

At the third stage of enlightenment, at the third step of Satori, our individual river flowing silently, suddenly reaches to the Ocean and becomes one with the Ocean.
At the third Satori, the ego is lost, and there is Atma, pure being. You are, but without any boundaries. The river has become the Ocean, the Whole.
It has become a vast emptiness, just like the pure sky.
The third stage of enlightenment happens when you have become capable of finding the inner being, the meditative quality within, the gap, the inner silence and emptiness, so that it becomes a natural quality.
You can find the gap whenever you want.
This is what tantra callas Mahamudra, the great orgasm, what Buddha calls Nirvana, what Lao Tzu calls Tao and what Jesus calls the kingdom of God.
You have found the door to God.
You have come home.

Swami Dhyan Giten