What does Luke 17:24 mean?
The Pharisees have asked Jesus when the kingdom of God will come. Jesus replies that the kingdom of God isn't what they think—it's not a war that drives the Romans out and returns Israel to independent prosperity. The inauguration of God's kingdom on earth began with Jesus' birth and is in their midst as a quiet movement comprised of Jesus' teachings and miracles (Luke 17:20–21).Now, Jesus talks to His disciples about what the fulfillment of God's kingdom will look like when He returns. The entire world will know; it will not be subtle. People will not need to personally spread the word that the Messiah has come (Luke 17:23). He will not hide in the wilderness or an inner room (Matthew 24:26). Anyone claiming Jesus has returned in some subtle or mysterious way will be wrong. His return will be as obvious as lightning illuminating the entire sky. "The sun will be darkened, and the moon will not give its light, and the stars will fall from heaven, and the powers of the heavens will be shaken" (Matthew 24:29).
First, however, the Messiah will be rejected. This generation of religious leaders—those speaking to Jesus in person during His earthly life—will reject and kill their own savior (Luke 17:25). Years will go by while Jesus' followers hope for His return (Luke 17:22). Then He will come, suddenly, when no one expects it (Luke 17:26–30).
Matthew 24:27 records Jesus giving a similar description during the Passion Week. It's not certain if Luke's account here happened earlier in Jesus' ministry or if he placed Jesus' words in Matthew 24 in this section and put the rest in chapter 21.