Passage
Iesus answered, Are there not twelue houres in the day? If a man walke in the day, hee stumbleth not, because he seeth the light of this world.
John 11:9 (GNV)
Nearby Context
John 11:7 Then after that, said he to his disciples, Let vs goe into Iudea againe.
John 11:8 The disciples saide vnto him, Master, the Iewes lately sought to stone thee, and doest thou goe thither againe?
John 11:9 Iesus answered, Are there not twelue houres in the day? If a man walke in the day, hee stumbleth not, because he seeth the light of this world.
John 11:10 But if a man walke in the night, hee stumbleth, because there is no light in him.
John 11:11 These things spake he, and after, he said vnto them, Our friend Lazarus sleepeth: but I goe to wake him vp.
Study Lenses
The verse centers on "world", "light", "iesus", "answered", "twelue", "houres", "walke", and "stumbleth". It is saying that the verse draws attention to "world" and "light", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 8's "The disciples saide vnto him Master the..." into verse 10's "But if a man walke in the...", 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.