Passage
Again, therefore, Jesus spake to them, saying, `I am the light of the world; he who is following me shall not walk in the darkness, but he shall have the light of the life.'
Again, therefore, Jesus spake to them, saying, `I am the light of the world; he who is following me shall not walk in the darkness, but he shall have the light of the life.'
John 8:10 And Jesus having bent himself back, and having seen no one but the woman, said to her, `Woman, where are those--thine accusers? did no one pass sentence upon thee?'
John 8:11 and she said, `No one, Sir;' and Jesus said to her, `Neither do I pass sentence on thee; be going on, and no more sin.'
John 8:12 Again, therefore, Jesus spake to them, saying, `I am the light of the world; he who is following me shall not walk in the darkness, but he shall have the light of the life.'
John 8:13 The Pharisees, therefore, said to him, `Thou of thyself dost testify, thy testimony is not true;'
John 8:14 Jesus answered and said to them, `And if I testify of myself--my testimony is true, because I have known whence I came, and whither I go, and ye--ye have not known whence I come, or whither I go.
The verse centers on "world", "light", "darkness", "again", "therefore", "jesus", "spake", and "saying". It is saying that the contrast between light and darkness marks a real divide in how people respond to God's work.
The nearby context moves from verse 11's "and she said No one Sir and..." into verse 13's "The Pharisees therefore said to him Thou...", so "world" and "light" belong inside that flow. In John context, the local focus is the identity of Jesus, new birth, eternal life, and belief and unbelief.
A plain takeaway is to answer the verse's own emphasis on "world" and "light" with trust shaped by these words, not by a vague optimism outside the passage.