Bandhas

[Gladius]

Is applying the bandhas just by themselves to break blockages safe?

 

[Zirgohed]

Bandhas cannot break blockages on their own, so they are absolutely safe. To activate their full effect, combine them with mantra vibration, breathing exercises, and energy practices.

 

[Marcusfortis]

As explained by @Zirgohed. The Bandhas are breathing and meditation aids to amplify and direct energy.
Please read the below link, especially the content on the "Jalandhara bandhas":

Bandhas

 

[Marcusfortis]

Also HPS Lydia Coventina's sermon mentioning this is very informative:

Piercing the Granthis With Bandhas

The Granthis (pronounced grahnt-hee) are energetic “knots” which in their healthy state hold our consciousness within our physical body. These are located at the approximate location of the Muladhara to Svadhisthana Chakras (Brahma Granthi), Manipura to Anahata Chakras (Vishnu Granthi), and...

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