Summary: Jesus’ return will result in millions of believers "missing" which will create in world tumult.
1 Th. 4:17 (and others)
We live in an age when people are getting caught up into so many different things - drugs... cults... crimes... etc. Those are negative things, but what I really want to talk about is something that we look forward to being caught up in - the rapture!
Vine’s Expository Dictionary gives the following definition for this word harpazo: "(it) is said of the act of the Spirit of the Lord in regard to Philip in Acts 8:39 (quickview)  (the Spirit of the Lord caught away Philip); of Paul being caught up to Paradise in 2 Corinthians 12:2 (quickview) , 4; of the Rapture of the saints at the return of the Lord in 1 Thessalonians 4:17 (quickview) of the rapture of the man-child in the vision of Revelation 12:5 (quickview) ."
In his book The Positive Side of Prophecy David Lewis states, "harpazo is better translated, ‘caught or snatched up by forceful seizure.’" He adds "The context seems to allow further amplification, ‘caught away forcefully in a state of ecstacy’"!
One morning the world may awaken, open its doors, and find a shocking front page newspaper report something like this -
"It has been reported that since approximately 3:15 this morning, suddenly, and without warning or trace, multiple millions of persons across the communicating world have disappeared from their homes, places of employment, and many even abandoning their means of transportation.
The United Nations has called it a global calamity. The President of the United States has declared the nation to be in a state of emergency. The armed forces are being dispatched throughout the country to maintain social order and to clear away the rubble left from the tremendous amounts of collisions resulting from the abandoned vehicles, trains and planes which were in motion at the time of the mysterious disappearance." -GB
Nave’s Topical Bible gives some 40 Scripture references for the return of Jesus. For our purposes we will only look at a few -
Jn. 14:2-3 In my Father’s house are many rooms; if it were not so, I would have told you. I am going there to prepare a place for you. 3 And if I go and prepare a place for you, I will come back and take you to be with me that you also may be where I am.
1 Cor. 15:51-52 Listen, I tell you a mystery: We will not all sleep, but we will all be changed-- 52 in a flash, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, the dead will be raised imperishable, and we will be changed.
The SEB says, We will be changed instantly, like the twinkle in someone’s eye. That last trumpet will sound. Then people will rise from death, never to die again.
1 Thes. 4:16-17 For the Lord Himself will come down from heaven, with a loud command, with the voice of the archangel and with the trumpet call of God, and the dead in Christ will rise first. 17 After that, we who are still alive and are left will be caught up together with them in the clouds to meet the Lord in the air. And so we will be with the Lord forever.