‘Kha' denotes Akasa, and ‘Chari' denotes movement. In the Akasa, the Yogi runs. The Akasa holds the tongue and the subconscious. As a result, it's known as Khechari Mudra.

Only a man who has completed the preliminary exercise under the direct supervision of a Guru who practices Khechari Mudra may perform this Mudra. The first step in this Mudra is to make the tongue so long that the tip of the tongue touches the gap between the two brows. 

Every week, the Guru would gradually cut the lower tongue tendon with a bright, clean knife. The cut edges can not join together again after being sprinkled with salt and turmeric powder. Cutting the tongue's lower tendon once a week for six months can be performed on a daily basis. 

Draw out the tongue by rubbing it with fresh butter. Take the tongue between your fingertips and move it back and forth. Milking the tongue entails grasping it and drawing it out, similar to how a milkman milks a cow's udder. You will lengthen the tongue in any of these ways to meet the forehead. This is the first part of the Khechari Mudra.

Then, when seated in Siddhasana, turn the tongue upwards and downwards until it touches the palate, close the posterior nasal openings with the reversed tongue, and focus the eyes on the gap between the two eye-brows. 

Prana can now go across the Sushumna Nadi, leaving the Ida and Pingala behind. The breathing will come to a halt. The tongue is resting on the mouth of the nectar well. Khechari Mudra is the name of the mudra.

The Yogi is cured of fainting, hunger, thirst, and laziness after practicing this Mudra. He is unaffected by infections, decay, aging, or death. 

This Mudra transforms an individual into an Oordhvaretas. Even virulent poison would not kill the Yogi because his body is packed with nectar. Yogins receives Siddhis from this Mudra. The greatest of all Mudras is Khechari.

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