Paul concluded his letter to Timothy by asking him to be true to Christ until he appears. He told Timothy that when Christ appears, after having laid aside all his human limitations, he will be seen as dwelling in unapproachable light.
Throughout the Bible light is presented as the basic metaphor for God’s perfections. In Ephesians 5:9 Paul says light stands for every kind of goodness, righteousness, and truth.
Throughout his Gospel John used light and darkness as the counterparts of grace and sin. By law the Last Supper could not begin until after nightfall. So, when, well into the evening, Judas went out, and John commented, “It was night.” He meant it was night in the soul of Judas.
Psalm thirty-six, in addressing God, says, “In your light we see light.” John repeated that idea in the Prelude to his Gospel when he said, “What came to be through him was life, and this life was the light of the human race.” There, John is telling us that the life of Christ is the source of the energy that powers our minds and our movements. We are powered by him, in the same way this city’s TV’s, computers and street lights are powered by JEA.