The Yogas of Sleeping and Rising

Another reason for beginning the practice of Vajrayogini at night is that during sleep the clear light mind of sleep manifests naturally and, with training, this mind can be used to progress along the spiritual path towards the realizations of example clear light and meaning clear light. One of the main reasons for practising Vajrayogini Tantra is to gain these realizations.

Venerable Geshe Kelsang Gyatso Rinpoche