WHAT DID JESUS MEAN? (1)
'I am the light of the world. Whoever follows me will never walk in darkness, but will have the light of life.' John 8:12
Darkness and light are used by Jesus, as in the rest of the Bible, as descriptions of what it means to live our lives either:
(1) ignorant of God and His ways (this is 'darkness'),
or (2) to live in the knowledge of what God is like; what He has done to tell us the truth about the world, including ourselves; and how we may know Him personally (this is 'light').
So Jesus is saying that he has come to bring us from the darkness of ignorance (about God) and death, into the light of knowledge (of God) and life. He has achieved that by His life, death and resurrection.
Jesus taught us what God is like and how we may know Him for ourselves. He called this 'entering the Kingdom of Heaven'.
By our nature we do not live consciously allowing God to rule over our lives. But as our Creator and God He is entitled to our allegiance and devotion. So we owe Him a debt, which if unpaid, will result now in having to live without His wisdom and care, and finally in our condemnation on Judgement Day. On the Cross Jesus died in our place to pay the debt we owe. If we put our trust in Him for ourselves and determine to live with God as our Ruler, we will be forgiven our debt, given God's Spirit to dwell within us, and declared 'not guilty' on Judgement Day. This present live, lived for Him, and the promise of future glory is what Jesus called 'eternal life'.