8:12 {4} Then spake Jesus again unto them, saying, I am the light of the world: he that followeth me shall not walk in darkness, but shall have the light of life.
(4) The world, which is blind in itself, cannot come to have any light but in Christ alone.
8:12 I am the light of the world. He then began his discourse to the people assembled. See notes on Mt 5:14 Joh 1:7-10.
8:12 He that followeth me shall in nowise walk in darkness - In ignorance, wickedness, misery: but shall have the light of life - He that closely, humbly, steadily follows me, shall have the Divine light continually shining upon him, diffusing over his soul knowledge, holiness, joy, till he is guided by it to life everlasting.
8:12-16 Christ is the Light of the world. God is light, and Christ is the image of the invisible God. One sun enlightens the whole world; so does one Christ, and there needs no more. What a dark dungeon would the world be without the sun! So would it be without Jesus, by whom light came into the world. Those who follow Christ shall not walk in darkness. They shall not be left without the truths which are necessary to keep them from destroying error, and the directions in the way of duty, necessary to keep them from condemning sin.