John 9:5

When I am in the world, I am the light of the world.

This is the second of the great "I am's" of John. For the list of these, see under John 8:12.

When I am in the world ... has the meaning of "as long as I am in the world" (KJV), an admission that there would come a time when Jesus would be no longer on earth; but that has reference only to his physical life. Such was the glory of Christ that, through the preaching of his apostles, the light would continue to shine unto all generations.

I AM THE LIGHT OF THE WORLD

The world cannot do without Jesus. He is as vital and necessary as the sun itself is to the physical world. All energy and life derive from him. See further discussion of this under John 8:12.

I. This metaphor reveals Jesus as God. Only of one identified with deity could it be said of him that he is the light of the world. The Old Testament made it clear that only God is light: "Jehovah is my light and my salvation" (Psalms 27:1); and an apostle identified God as "the Father of lights" (James 1:17). Therefore, when Jesus said, "I am the light of the world," he forever lifted himself above the category of mere mortality. Only a lunatic, or the world's true Saviour, could sincerely have said such a thing as this; and the receding centuries have left no doubt that the Redeemer said it and that he is indeed the world's light. He was God come in the flesh.

II. This metaphor teaches the sinless and undefiled nature of Christ, light being the only thing that may fall upon rottenness and corruption and itself remain uncontaminated. The Light of the world shines upon the wretched ugliness of our shameless world, saves it, changes it, and lifts it up, but is not himself contaminated. No matter how squalid the room in which the light shines, the light remains pure. Peter wrote:

And we have the word of prophecy made more sure; whereunto ye do well that ye take heed, as unto a lamp shining in a dark place (Greek: squalid room), until the day dawn and the Day-star arise in your hearts (2 Peter 1:19).

III. This light obligates all who see it. Men may be pardoned for stumbling in darkness; but those who close their eyes against the light commit a sin against nature as well as against God. The obligation imposed by the presence of light may not be assumed or rejected by men, for the very existence of light carries the inherent requirement that men shall walk in it. Jesus summed it up thus: "I am come a light into the world, that whosoever believeth in me may not abide in darkness" (John 12:46).

IV. Jesus is the light of the world eternally, for even in heaven, "the Lamb is the light" of the eternal city (Revelation 21:23). Bonar's hymn catches the mystery of this thought perfectly:

Light of the world, forever, ever shining, There is no change in thee. True light of life, all joy and health enshrining, Thou canst not fade nor flee.

V. This metaphor is an apt figure of the universality of the gospel, there being no place on earth where light cannot reach. Similarly, the saving message of Christ shines throughout all the earth. The witness of the calendar, of Christendom, of history, of the progress of civilization, etc. - imperfect as the witness surely is, it is nevertheless undeniably universal. As John said of Jesus, he is "even the light which lighteth every man" (John 1:6-9).

VI. Men are commanded to respond to the light. They should believe on the light and become sons of light (John 12:36); they should walk in the light (1 John 1:6,7); they should put on the whole armor of light (Romans 13:12); and they should arise and shine in the reflected glory of the light (Isaiah 60:1). The import of all this is that all men should exhibit an obedient faith in Christ.