Nidra Kriya Sadhana

Nidra Kriya Sadhana (a form of meditation) is the second stage of this practice, which involves sleep and stability. It’s the practice of being a witness to those actions.
Actions during sleep:
* Seeing dreams spontaneously
* Not seeing dreams spontaneously
* Seeing dreams by choice
* Not seeing dreams by choice
* Control over the subtle body
… and so on.
So, in all of these actions, the practice is to be a witness, and it’s during the state of sleep that the subtle difference between the body, mind, and the witness can be easily understood.