Stretching of Tongue
In Khechari Mudra
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Before Khechari Mudra The position of tongue is outlined in yellow
With Khechari Mudra The position of tongue is outlined in yellow
With Khechari Mudra, notice the formation of an 'Om' like impression (highlighted in yellow)
Khechari Mudra is a key condition of Kriya practice; it is called "the King of mudras." Hatha Yoga Pradipika says, "There is no mudra higher than Khechari."
The direct translation of Khechari means - 'kha' which means 'space', and 'chari' which means 'movement'. So it means 'movement into the space'.
There are several stages of mastering Khechari Mudra. It starts from "swallowing of the tongue", then comes the installation of the breath flow in Sushumna (central channel, connecting brain and nervous system), and stopping of the breath (Kevala Kumbhaka). The finishing stage is the state of Unmani, where the mind is absorbed in its original cause Khechari Mudra is actually the beginning of Kriya.
Between Vishuddha and Ajna Chakra there is space, which should be bridged by taking the tongue inside.
This is the first stage of Khechari. Without it Sushumna does not exist: it is disconnected and is in two parts. For this reason, the beginning practices of Kriya Yoga do not include a number of pranayams and bandhas. They will not work without the locked tongue in Khechari, or they can even do some damage. After Sushumna is locked, the next stage - the awakening of the subtle body, starts.