He stayed a couple of days longer when He heard Lazarus was sick. Then Jesus decided to go to Judea. His disciples quickly reminded him that the Jews were trying to stone him just a few days ago. Why did Jesus respond to his disciples by asking them "Are there not 12 hours in a day?" I understand the significance of walking in the light and darkness (i.e. walking with Christ vs. sin). Is there something about the journey back to Judea that one should only walk during the day? Or was it too dangerous to walk at night due to terrain or thieves/robbers/mercenaries?
Walking in the light of God's will and word was Jesus' deepest desire (Jn 17:4), even though doing so would culminate in His death. His goal was ultimately to accomplish the work His Father sent Him to do, thereby pleasing His Father (see Jn 8:29) and bringing many sons to glory (He 2:10).
Jesus' disciples feared for His safety, and rightly so. Jesus, on the other hand did not. He was certainly in the eleventh hour of His earthly sojourn, but He was determined to continue walking in the light of His Father's will, even if it meant certain death.
As for His enemies who hated Him without a cause, Jesus would leave them to stumble on in the darkness of their disobedience, the disobedience to which they were appointed (1 Pe 2:8b); to them, Jesus was a rock of offense and stumbling (1 Pe 2:8a). They preferred the darkness because their deeds were evil (Jn 3:19), and they were determined to kill Jesus, despite His being the Light of the world (Jn 8:12; 9:5).
In conclusion, the timeframe of which Jesus spoke when he asked His disciples "Are there not 12 hours in the day?" drew attention to His time being short. The spiritual darkness of the cross was imminent. While His soul shrank from what lay ahead, He was determined to finish His work, knowing that the darkness could not overpower the Light of life which emanated from the cross (see Jn 1:4,5; 8:12).
He continued, saying: 'Are there not twelve hours in a day? If anyone walks around in the daytime, he does not stumble, because he sees the light of this world. But if anyone walks around at night, he stumbles, because the light is not in him.'
Meaning he himself is the light. There is no stumbling for him. Those of the darkness will stumble over him. But not yet. As long as the Father lets him shine, he continues his work until his day is over.