17:20-37 When Jesus was asked by the Pharisees when the kingdom of God was coming, he answered them, "The kingdom of God does not come with signs that you can watch for; nor will they say, 'Look here!' or 'Look there!' For--look you--the kingdom of God is within you."
He said to his disciples, "Days will come when you will long to see one of the days of the Son of Man and you will not see it. And they will say to you, 'Look there! Look here!' Do not depart, and do not follow them. For, as the flashing lightning lights up the sky from one side to another, so shall be the Son of Man in his day. But first he must suffer many things and be rejected by this generation. Even as it was in the days of Noah, so it will be in the days of the Son of Man. They were eating, they were drinking, they were marrying, they were being given in marriage, until the day on which Noah entered the ark and the flood came and wiped them all out. In the same way, so it was in the days of Lot. They were eating, they were drinking, they were buying, they were selling, they were planting, they were building, but, on the day on which Lot went out of Sodom, fire and brimstone rained from heaven and wiped them all out. It will be the same on the day on which the Son of Man is revealed. If, on that day, anyone is on the housetop, and his goods are in the house, let him not come down to take them. In the same way, if anyone is in the field, let him not turn back. Remember Lot's wife! Whoever seeks to gain his life will lose it, but whoever loses it will preserve it alive. This is the truth I tell you--on that night there will be two in one bed. One will be taken and the other will be left. Two women will be grinding together. One will be taken and the other left." They said to him, "Where, Lord?" He said to them, "Where the body is, there the vultures will be gathered together."
Here are two very difficult passages.
In Luke 17:20-21 Jesus answered the question of the Pharisees as to when the kingdom of God would come. He said that it would not come with signs that watch for. The word he used is the word used for a doctor watching a patient for symptoms of some disease which he suspects.
We are not quite sure what Jesus went on to say. The Greek may mean two things.
(a) It may mean, the kingdom of God is within you. That is to say, the kingdom of God works in men's hearts; it is to produce not new things, but new people. It is not a revolution in material things that we are to look for, but a revolution in the hearts of men.
(b) It may mean, the kingdom of God is among you. That would refer to Jesus himself. He was the very embodiment of the kingdom, and they did not recognize him. It was as if he said, "The whole offer and secret of God are here--and you will not accept them."
Luke 17:22-37 speak of the Second Coming of Jesus. Out of this difficult passage we can pick only the things which are certain--and in truth they are enough.
(i) There will be times when the Christian will long for the coming of Christ. Like the martyred saints he will cry out, "How long?" ( Revelation 6:10 .) But he will need to learn to light a candle of patience and wait. God takes his own time.
(ii) The coming of Christ is certain, but its time is quite unknown. Speculation is vain. People will come with false prophecies and false predictions; but we must not leave our ordinary work to follow them. The best way that Christ can come upon a man is when he is faithfully and humbly and watchfully doing his duty. As a great commentator said, "No man will foresee it, and all men will see it."
(iii) When that day comes the judgments of God will operate, and of two people, who all their lives lived side by side, one will be taken and the other left. There is a warning here. Intimacy with a good person does not necessarily guarantee our own salvation. "No man can deliver his brother." Is it not often true that a family is apt to leave the duties of church membership to one of its number? Is it not often true that a husband leaves the duties of the church to his wife? The judgment of God is an individual judgment. We cannot discharge our duty to God by proxy nor even by association. Often one will be taken and another left.
(iv) When they asked Jesus when all this would happen, he answered by quoting a well-known proverb. "Where the body is, there the vultures will be gathered together." That simply meant that a thing would happen when the necessary conditions were fulfilled. That means for us that God will bring Jesus Christ again in his good time. We cannot know that time; we dare not speculate about it. We must live so that whenever he comes, at morning, at midday or at evening, he will find us ready.
-Barclay's Daily Study Bible (NT)