Vijnana Bhairava Tantra
91: When one fixes his mind freed of all props on the end of the visarga of a letter coupled with visarga, then being completely introverted, he enters the eternal Brahman.
92: When one concentrates on one's self in the form of a vast sky, unlimited in all directions, then the citi sakti freed of all props reveals herself.
93: If one pierces at first any limb with sharp-pointed needle etc., and then concentrates on that very spot, then owing to the intensity of one-pointed awareness one has access to the pure nature of Bhairava.
94: One should contemplate thus Within me the inner psychic apparatus consisting of citta, etc. does not exist. In the absence of thought-constructs, he will be completely rid of all thought-constructs (vikalpas) and will abide as pure consciousness (suddha caitanya) which is his essential Self.
95: Maya is delusive, the function of kala is limited activity (of vidya, it is limited knowledge etc.). Considering the functions of the various tattvas (constitutive principles) in this way, one does not remain separate any longer.