Just as a river has a source, so the river of consciousness has a source. It descends from Cosmic Consciousness, the consciousness of God that is beyond all creation. When Cosmic Consciousness comes into the realm of matter- into each of the atoms that make up the planets and island universes, and the different forms of plant, animal, and human life- that Consciousness is called Christ Consciousness. When Christ Consciousness descends into the soul and pure mind of man, it is called superconsciousness. When superconsciousness descends into the realm of imagination, it is called subconsciousness. When subconsciousness descends into the muscular and sensory phase of human life, it is called human or waking consciousness. When waking consciousness becomes attached to the senses and material things, it is called worldly consciousness, and when it is used to harm oneself or others, it is evil consciousness. But when it is used to do good things and to produce attunement with God, then it is called spiritual consciousness.
Our souls are like derelicts floating on this river of consciousness, going farther and farther away from their source in Spirit towar the rocks of misery. The only way to stop this evolutional floating downward in the stream of consciousness is to swim against that current, back to the source in Spirit.
Paramahansa Yogananda