Ksurika Upanishad is the 31st among 108 Upanishads and forms part of Krishna Yajur Veda. It is one of the twenty Yoga Upanishads. The Sanskrit word Ksurika means Knife. This Upanishad prescribes yoga that will cut asunder the bondage between Atman and rebirth.
Contemplation on Marma Sthana
The mode of yoga taught in Ksurika Upanishad is Yoga of contemplation on vital body parts.
Secure a silent place in seclusion. Assume any suitable posture. Withdraw all senses of organs. Restrict your mind from wandering and keep it in your heart. Breathe in and mentally chant the ohm of four matras. Hold in the air slightly lifting your chest, hip, and neck, and breathe out gradually.
The Upanishad explains the kriya of contemplation on Marma Sthana (vital parts) of the body. The idea of yoga-nidra given by contemporary yoga gurus is based on this technique only. Having brought his sense organs under control and making his Mind and Prana firm, the yogi should perform Dharana on toes, two ankles, shanks, Knees, thighs, Muladhara, and Swathistana. He should fix Mind, Prana, and Atman in Manipura till mastery.
Rules of Contemplation
The Yogi should take only one part at a time for Dharana. To move to the next part, he should cut off the earlier part.
Then Susumna Nadi of white color surrounded by ten other Nadis of different colors which are very subtle and fine, should be mediated. The Yogi should take Dharana on Anahata the red lotus. Likewise, he should take the next Lotus Vishuddha for meditation. Then, Anja and Sahasrara.
While meditating on each Marma sthana, the Yogi should contemplate on the Inner Eye and mind, and Prana on that part, which is nothing beyond the Brahman. The Yogi gets this knowledge only when he has mastery over the kriya. We have already seen that the Yogi should cut off the contemplation of the earlier part while moving to the next part. However, there is one exception to this rule. The Yogi should not cut off Susumna. By doing this kriya, the yogi will become adept in Astanga Yoga. He, having cut off his bondage with the knife of Om and being sharpened by the practice of pranayama, does not bind it again.