Words by Jigme Lingpa, the great Dzogchen Master:

“Here is the essence of the maha ati tantra,
The innermost heart of Padmakara’s teachings,
The life-force of the
dakinis.
This is the ultimate teaching of all the nine vehicles.
It can be transmitted only by a guru of the thought lineage
And not by words alone.
Nevertheless, I have written this
For the benefit of great meditators
Who are dedicated to the highest
teaching.
This teaching was taken from the treasury of
dharmadhatu
And is not created out of attachment
To theories and philosophical abstractions.”

From Mudra, by Chogyam Trungpa:

If the meditator is able to use whatever occurs in his life as the path, his body becomes a retreat hut. He does not need to add up the number of years he has been meditating and does not panic when “shocking” thoughts arise. His awareness remains unbroken like that of an old man watching a child at play.

As is said in a maha ati text: “Complete realization is like unchanging space.”

The yogi of maha ati may look like an ordinary person but his awareness is completely absorbed in nowness. He has no need of books because he sees apparent phenomena and the whole of existence as the mandala of the guru. For him there is no speculation about the stages on the path. His actions are spontaneous and therefore benefit all sentient beings. When he leaves the physical body his consciousness becomes one with the dharmakaya, just as the air in a vase merges with the surrounding space when the vase is broken.

Source:
https://www.beezone.com/Trungpa/innermost_essence.html