The Subtle Body (or bodies) are the intangible layers of energy which seem to surround the physical body and create the aura. It is commonly said that these layers are like an onion, and that when you peel one away, you'll reach the next, but this is not accurate.

 As you extend inward, the one before is also present within the next layer.  As you go inward, towards the first layer (the etheric) it will be the densest because it is contained by the other subtle bodies. And of course, there is the physical body, which is the densest of them all.

Various philosophical systems describe as many as seven bodies: three physical, three spiritual, and the astral connecting them. For the sake of clarity and simplicity we set forth three levels beyond the physical: the etheric, the astral and spirit. The astral body is the bridge between the

on the Subtle Bodies

Astral body
Etheric Body
Higher Self

physical and spiritual. These bodies, though connected, dwell in their own extended worlds. As each layer extends outwards, it vibrates at a higher rate. So the etheric body vibrates at a much lower frequency then the astral body. Energy can be transmuted between all bodies.

The Linga Sharira is the invisible double of the human body, often referred to as the etheric body, doppelgänger or bioplasmic body and is a mirror of the physical body. Each vehicle changes as changes are made to the other vehicle. The linga sarira can be separated or projected a  distance from the body. When separated from the body it can handle physical objects and can easily be seen in the physical world  When wounded by a sharp object, the wound will be reflected in the physical body,  At death, it is discarded together with the physical body and eventually disintegrates or decomposes.

The Mayavi-rupa is the astral body and is the vehicle of both unconscious thought and of the emotions and desires, drawing at one and the same time from them. The Mayavi-rupa can be projected from the body to travel through all the worlds beneath Spirit. It is said by many that this body is composed of two elements: the higher and the lower. The higher spiritual elements are an expression of spirit while the lower part, containing the unconsious and emotional elements, is the source of "ghosts" or apparitions of the dead.

Spirit is eternal, unchangeable and ever-present, external to time and space.