Jesus made use of the occasion of the Feast of the Tabernacles to instruct people he was the light of the world (Jn 8:12). During the feast, the temple courtyard had four large golden menorahs, having seven torches each. These twenty-eight big torches illuminated a wide area. The light from them and was visible from all around the city as a “pillar of fire.”
The beam of light from the four menorahs in the Temple reminded the people of the presence and guidance of God as pillar of fire at night in the wilderness. Jesus said on this occasion that he is the light (not a light) of the world (not just in Jerusalem or for the Jews, but for people all over the world). Thus, Jesus replaced the four menorahs that illuminated the Holy place of the Temple. Only one sun is necessary to illumine the world. So also, Jesus is the only source of spiritual light.
Jesus is light of not just the Christians, but of the world. That spiritual light continues to illumine the humans. His teachings are relevant even after two thousand years. His moral, spiritual, and charitable values influence the world through the Christians, and it will continue. He promised that those who follow him “will not walk in darkness, but will have the light of life” (Jn 8:12).