Jesus told his disciples they were the light of the world.See Matt. 5:14. From the world's standpoint they weren't particularly good candidates for being its light!
Possibly, argued worldly wisdom, the great Alexander or Greek civilization itself could have been said to fit that description. Or perhaps the Emperor Augustus could properly have been called the light of the world. After all, the poet Virgil had written of him, "And here, here is the man, the promised one you know of—Caesar Augustus, son of a god, destined to rule and bring back the age of gold . . . ." The Aeneid, Book VI, lines 791-793.
But Christ Jesus' disciples were—and indeed still are the light of the world. Because of their obedience to the Christ, or spirit of God expressed by Jesus, they became light to a world stumbling in the darkness of supposed life in matter.