“John’s Gospel speaks of Jesus’s miracles as ‘signs.’ Signs are often miniature, even coded, representations of the reality to which they point. So they are here. For a moment, Jesus, the Light of the World (John 8:12; 1:5), shines in a way that irresistibly overcomes the world’s darkness, and says, ‘This is who I am and this is what I will do.’
One day Christ will return in the full glory of His resurrection power. The light will be switched on permanently. The Lamb of God who took away the sin of the world will be present in the new heavens and earth as their lamp. Neither sun nor moon will be needed (Rev. 21:23). As He will be the Life, so He will be the Light of the new world.”
–Sinclair Ferguson, In Christ Alone: Living the Gospel Centered Life (Orlando: Reformation Trust, 2007), 71.