Passage
In him was life, and the life was the light of men,
In him was life, and the life was the light of men,
John 1:2 this one was in the beginning with God;
John 1:3 all things through him did happen, and without him happened not even one thing that hath happened.
John 1:4 In him was life, and the life was the light of men,
John 1:5 and the light in the darkness did shine, and the darkness did not perceive it.
John 1:6 There came a man--having been sent from God--whose name <FI>is<Fi> John,
The verse centers on "light" and "life". It is saying that the verse draws attention to "light" and "life", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 3's "all things through him did happen and..." into verse 5's "and the light in the darkness did...", so "light" and "life" 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 "light" and "life" with trust shaped by these words, not by a vague optimism outside the passage.