What does Matthew 24:3 mean?
The passage that begins with this verse is often called the Olivet Discourse. Christ is sitting on the Mount of Olives as He teaches. From His position, Jesus can see the entrance to the temple. In the previous verse, He predicted that the temple would be fully and utterly destroyed, without one stone being left on top of another. This sad prophecy would come true in AD 70 when the Roman Empire attacks Jerusalem, dismantling the entire temple in the process.In response to that detail, apparently, the disciples ask Jesus a two-part question. His long and involved answer focuses on future events for the disciples and Himself. Beginning in the next verse, the entire text of Matthew is devoted to Jesus' words through the end of chapter 25.
The disciples ask, first, when the temple will be destroyed and second, how they will know Christ is returning to complete the end of days. It's likely the disciples thought the judgment Jesus had been describing would happen at the same time as His return. Jesus' answer doesn't confirm that this is necessarily true. The disciples seem to grasp the basic idea that Jesus was leaving and coming back, though their understanding of His impending death and resurrection continues to be limited.