The Light of the Body:

This scripture reveals a lot about a different sort of awareness.  It is a consciousness we can attain that complements our baptism. 

There is a baptism of the body, a baptism of the mind, and, a baptism of the soul. I believe, in this passage, Jesus Christ is talking about the baptism of the mind.

It becomes possible when the Holy Spirit helps our mind become sound. When the ears attain the ability to see, and,  the  eyes achieve  the means to hear, the mind acquires a new perspective. 

And when the mind is sound, the whole body is illuminated by being able to discern what is right from wrong.  In other words,  it learns to listen to the voice of  its conscience...

...A conscience that has God's word and law imprinted on it.