“To whatever cause an illness may be due, material or mental, external or internal, it must, before it can affect the physical body, touch another layer of the being that surrounds and protects it. This subtler layer is called in different teachings by various names, — the etheric body, the nervous envelope. It is a subtle body and yet almost visible. In density something like the vibrations that you see around a very hot and steaming object, it emanates from the physical body and closely covers it. All communications with the exterior world are made through this medium, and it is this that must be invaded and penetrated first before the body can be affected. If this envelope is absolutely strong and intact, you can go into places infested with the worst of diseases, even plague and cholera, and remain quite immune. It is a perfect protection against all possible attacks of illness, so long as it is whole and entire, thoroughly consistent in its composition, its elements in faultless balance. This body is built up, on the one side, of a material basis, but rather of material conditions than of physical matter, on the other, of the vibrations of our psychological states. Peace and equanimity and confidence, faith in health, undisturbed repose and cheerfulness and bright gladness constitute this element in it and give it strength and substance. It is a very sensitive medium with facile and quick reactions; it readily takes in all kinds of suggestions and these can rapidly change and almost remould its condition. A bad suggestion acts very strongly upon it; a good suggestion operates in the contrary sense with the same force. Depression and discouragement have a very adverse effect; they cut out holes in it, as it were, in its very stuff, render it weak and unresisting and open to hostile attacks an easy passage.
It is the action of this medium that partly explains why people often feel a spontaneous and unreasoning attraction or repulsion for each other. The first seat of these reactions is in this protecting envelope. Easily we feel attracted towards people who bring a reinforcement to our nervous envelope; we are repelled by those who disturb or hurt it. Whatever gives it a sense of expansion and comfort and ease, whatever makes it respond with a feeling of happiness and pleasure exercises on us at once an attraction; when the effect is in the contrary sense, it responds with a protecting repulsion. This movement, when two people meet, is often mutual. It is not, of course, the only cause of affinities, but it is one and a very frequent cause.”
“If we take the best instance, of someone who has unified his being completely around the divine Presence within him, who is now only one will, one consciousness, this person will have grouped around his central psychic being a fully developed and organised mind, an absolutely surrendered and collaborating vital and an obedient, docile and supple physical being. This physical being, as it is fully developed, will have a subtle body — what Sri Aurobindo calls the “true physical” — which will infinitely surpass the limits of its body and have enough suppleness, plasticity, balance to be able to adhere to the inner parts of the being and follow the movement of the soul in its... I don’t want to say in its ascent [after death], but in its peregrinations outside the body.”