When Jesus spoke again to the people, he said, “I am the light of the world.  Whoever follows me will never walk in darkness, but will have the light of life.”

I looked up the word “light” in the Greek.  It means a luminous force emanating from certain bodies which allow the eye to distinguish form and color.

Until Christ comes into a person’s life, that person is incapable of receiving spiritual light because he has no receptor.  In the new birth through salvation, we are given the capacity to receive this light.  So, in  John 8:12, Jesus is saying He is the Illuminator of men.  Life equals life in the absolute sense.  Life as God has it.  That which the Father has in Himself, and which is in the Incarnate Son.  Also, part of the explanation of this word includes the fact that sin involved the forfeiting of this God-life.

So, vs. 12 with the expanded definition reads like this: Whoever follows me will never walk in darkness, but I will be his Illuminator, and will give him as his possession, that which was forfeited by the sin of man, life as God possesses it.