The event that fits Jesus' description in Luke 17:34–35 is the Roman siege and destruction of Jerusalem in AD 70.

In that generation, just as Jesus warned in Luke 21:20–24 and

Matthew 24:15–21, the Romans surrounded Jerusalem and brought devastating judgment on the city. Those "taken" were taken in judgment, either killed or captured, while those "left" were the ones who escaped by heeding Jesus' warning to flee (Luke 21:21).

The parallel in Matthew 24:37–41 compares it to the days of Noah: the ones "taken" were those swept away in judgment, while the righteous remained alive. In Luke 17:37, when the disciples asked "Where, Lord?" Jesus answered, "Where the body is, there also the vultures will be gathered," pointing to the corpses that would fill Jerusalem under Roman slaughter.

So in the first-century context, this was not about a rapture to heaven, but about the separation of the righteous who obeyed Christ's warning from the wicked who perished in the Jewish-Roman War.