To read the texts click on the texts:2 John 1:4-9; Lk 17:26-37
This section starts with the examples of the days of Noah and Lot (17:26-29). Just as in the days of Noah and Lot the life of the people at that time proceeded normally and people were going about their daily business until all of a sudden the flood and brimstone and fire respectively destroyed the people, so it will be on the day when the Son of Man is revealed. This means that decisive action is absolutely necessary. There will be no turning back.
Lot’s wife who turned into a pillar of salt when she looked back (Genesis 19:26) is given as an example of the dangers of looking back. When the Son of Man does indeed come, then the choice of those who will be taken and those who will be left will be made.
In answer to the disciples’ question, “Where, Lord?” (17:37), Jesus answers with an enigmatic proverb, “Where the corpse is, there the vultures will gather” (17:37). The point of this proverb here seems to be that just as it is sure that vultures will gather where a corpse is found, as surely will the judgement of the Son of Man fall upon on the wicked.
Decisive action does not mean desperate action. It means steady and regular action. If one is at any given moment in time doing what one is supposed to do, it may be regarded as decisive action. A person engaged in such an activity is always ready.