The people who walked in darkness have seen a great light; those who dwelt in the land of the shadow of death, upon them a light has shined. (Isaiah 9:2)
Without doubt that light is Christ and His Word. That Word is a lamp to our feet and a light to our path. The Word of God gives light to this present life and the life of Christ gives light to eternal life. One teaches us how to live and the other gives us victory over death. Jesus said, "The light has come into the world, and men loved darkness rather than light, because their deeds were evil." Darkness is deceptive; in it we often think that we can hide our sin. We cannot. Because the light has come into the world, sin has been exposed. It cannot be hidden. No matter how dark the night of our sin, the light of the Dayspring will reveal it. "Through the tender mercy of our God, with which the Dayspring from on high has visited us; to give light to those who sit in darkness and the shadow of death, to guide our feet into the way of peace."
 Psalm 119:105
 John 3:19
 Luke 1:78
 Luke 1:78-79