Just as thoughts, send out vibrations to which there is a creative and attractive power, gratitude stimulates the field of etheric energy that surrounds you on a subtle level to bring into your life more of what brings you joy.
Just as we have a physical body, so we have an etheric body and the etheric body is made up of energy, of light.
In dream yoga we use the etheric double and go beyond the confines of the physical, it's very ecstatic.