It has been observed that all humans have any one of the four main types of consciousness. The first of these, which is common to almost everyone, is gross consciousness or body consciousness. The example of an actor illustrates what body consciousness is. An actor plays his given role on stage. If he is called upon to act as a king, he may use a costume to look like one, but in his mind he is not oblivious to the fact that he is not a king and is only playing that role. The folly of humans, however, is that while playing their roles in the drama of this world they identify themselves with their body, forgetting that they are souls.
The second kind of consciousness may be called intellectual consciousness. Intellectuals, scientists and the like experience this when they concentrate their minds on abstract ideas. When they do so, they are not conscious of their body, their relatives or worldly matters as their mind is fully occupied with one idea.
Then there is subtle consciousness. Devotees experience this when they are lost in contemplation of subtle deities, angels etc. During prayer or meditation, they rise above gross consciousness and feel elevated and uplifted. These devotees may not be conscious of their own body or the physical form of the deities they are worshipping, but in their intellect they see the subtle form of the deities.
The highest level of consciousness, which a yogi aspires to, is super consciousness, wherein one’s mind is turned to the incorporeal Supreme Soul. This is what is known, in one word, as yoga. A yogi is conscious of himself as a soul and of God as the Supreme Soul. Just as the insulation has to be removed from a wire in order to connect it to a source of power, one has to withdraw one’s consciousness from the body in order to establish a link with God.