There are five layers of koshas:
1 Annamaya -kosha (food sheath, Earth element) consists of your physical material body. It is fuelled by the food we eat.
2 Pranamaya- kosha ( vital sheath,water element)
This surrounds and penetrates the physical body as the vital energy which flows in and around the body.The practice of pranayama helps to keep this energy flowing freely , which also affects the health of physical body.
3 Manomaya-kosha (mental health,Fire element)
Even more subtle than the first two koshas, Manomaya- kosa consists of thinking mind and emotions
4 Vijnanamaya -kosha (intellect,/intuitive sheath, Air element)
Permeating the 3 denser layers (manomaya, pranamaya,and annamaya) is the home of our inner knowing and wisdom. It is this aspect of our being which knows life intimately at the deepest level and fromwhich we receive messages from beyond what ever mind could ever understand. within this sheath there is still illusion of duality, where there is a knower, the knowing,and the known. However through the process of asana,pranayama,dharana and then through meditation (dhyana) the mind becomes still and we can truely listen to silent messages.
The second and third sutras in the very first chapter in Patanjali’s Raja Yoga Sutras state:
1.2 Yogas chittavrittinirodha-
1.3 Tada drastuhsvarupe ‘vasthanam
5. Anandamaya-kossa (bliss sheath, ether/ space element)
Beyond the other 4 koshas and yet permeating and comprising them al It is free from our thoughts, emotions,energy and body and at the same time embracing them alll, is the sheath of bliss. This is the aspect of our being which we recognise as a deep inner peace and joy . It is the sweetness of all life that we feel when the mind is still-also known as satvic-ananda. It may be the super- conscious state of samadhi, the 8th limb of Raja Yoga.