An aura is an electromagnetic energy field that surrounds us all. Every aura is made up of 7 layers, each one with its own purpose and impact. The innermost layer is your physical body and less than an inch outside of it is the etheric layer, the densest layer. Following the etheric layer is the emotional layer, mental layer, spiritual or etheric temple layer, the celestial body and finally the ketheric body, which are also known as the subtle bodies. The Etheric energy system is connected to the emotional energy system and the mental energy system. The energy bodies are integrated and they speak to one another all the time.
The etheric body is the physical plane of the aura. Due to its close proximity, it is deeply connected to your physical body. It has ties to your physical health, all your bodily sensations, including pain and pleasure. It is linked with the root chakra, which among other things, is associated with our basic human needs. Our physical bodies and etheric bodies are so closely connected that sometimes the etheric body is called a metaphysical twin.
It is through the etheric body that prana or life energy can be absorbed into and distributed through the physical body. The etheric body thus serves as a channel for life energy to flow into the visible physical body we possess and are so attached to. The flow of prana throughout the etheric body is facilitated by fine bioplasmic meridians the workings of which are much like the workings of the blood vessels in the physical body. Yogic terminology refers to these channels or meridians as 'nadis'. These nadis are further classified into major and minor nadis. Just like we possess blood vessels and capillaries of varied importance and function in our tangible body, there is order in our etheric body as well. Prana (chi) thus provides nourishment to and invigorates the physical body in its totality through the effective functioning of the channels in the etheric body.
The etheric body and the physical body share an intimate bond of interdependence and what affects one, affects the other. This process of inter-related functioning works in accordance with the Law of Correspondence. Just as sickness in the etheric body is a precursor to sickness in the physical body, healing the etheric body heals the ailments in the physical body. The etheric body is thus a tetra-dimensional energy entity that serves as an integral counterpart of the physical body.