“For the Lord himself will descend from heaven with a shout of command, with the voice of the archangel and with the trumpet of God, and the dead in Christ will rise first. Then we who are alive, who remain, will be snatched away at the same time together with them in the clouds for a meeting with the Lord in the air, and thus we will be together with the Lord always. Therefore comfort one another with these words.” 1 Thessalonians 4:16-18
“Behold, I shew you a mystery; We shall not all sleep, but we shall all be changed, In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed. For this corruptible must put on incorruption, and this mortal [must] put on immortality” (1 Cor. 15:51-53).
These are very remarkable verses that describe the snatching away of the church to meet Christ in the air. This event is imminent, meaning that it could come at any time. It is unlike the second coming of Christ which needs certain events to take place before it can take place.
It is important to remember that rapture and second coming are similar but separate events. Both involve Jesus’ returning. Both are end-times events. The rapture is the return of Christ in the clouds to remove all believers from the earth before the time of God’s wrath. The second coming is the return of Christ to the earth to bring the tribulation to an end and to defeat the Antichrist and his evil world empire.
That is a very brief summary of two cataclysmic end-time events, but the above verses have a very important place in our lives today. Even though the rapture will come on us without warning and takes place at the beginning of the seven-year tribulation (some disagree, but they are not writing here this morning, so they can save their thoughts for their own devotionals), there are things that are going on inour world give us hints that the rapture could be soon upon us.
The word “maranatha” is a Syriac expression that means: “our Lord comes.” It was used as a greeting in the early church. When believers gathered or parted, they didn’t say “hello” or “goodbye” but “Maranatha!” It is too bad that Christians don’t have that same upward look today. How it would change the church if we all looked at the return of Christ with certainty and conviction. How differently would we look at all those around us. 
I have a friend who says, “See you here, there (pointing upward), or in air,” instead of goodbye. It is really the three choices two believers have- they will see each other on this earth, or in heaven, or in transit. It is a neat way to remember the “where” in “till we meet again.”
It is true that certain things must take place before the second-coming at the end of the tribulation and many of those things have already happened or are happening right now. The stage must be set for the tribulation and anyone who has even the slightest interest in prophesy and current events can see that the table is being set for the end times. For instance, the nation of Israel was scattered across the face of the earth, but yet just fewer than 60 years ago was brought back together and is today one of the most powerful nations in the world. That process of scattering a people then reestablishing them has never taken place before. That had to take place as a prerequisite before all the other events could occur.
So, why worry (oops, I mean think) about all this? Because we never know when the Lord will come again. It is important that we are looking for opportunities to share with those who do not know the Lord because the instant Christ comes that chance will be lost forever. In fact, if you share the gospel with someone and if that person put his belief in Christ, look up, because the word says that the rapture will not happen until the body of Christ is filled. That person that you just shared with might be the last one to fill it, and so we all might be leaving right then!
One of my favorite men of courage is the British explorer Ernest Shackleton. I have read
several books chronicling his incredible voyages to the South Pole. While on one of the voyages he had to leave a few men on Elephant Island because their ship was crushed and there was not enough room for the entire crew. He promised them that he would return. Later, when he tried to go back, huge icebergs blocked the way. But suddenly, as if by a miracle, the huge icebergs shifted and a channel opened in the ice and Shackleton was able to get through. His men, ready and waiting, quickly scrambled aboard. No sooner had the ship cleared the island than the ice crashed together behind them. Contemplating their narrow escape, Shackleton said to his men, “It was fortunate you were all packed and ready to go!”
They replied, “We never gave up hope. Whenever the sea was clear of ice, we rolled up our sleeping bags and reminded each other, ‘The boss may come today.'” That is the same attitude that we should have!
We should not fear the coming of The Lord because it will be a glorious event, but unlike Elephant Island, we do know that there will be many “left behind.” 
We should do all we can to make sure that our friends and family are not part of that number by living our lives for Christ and sharing Him in word and deed. What incredible verses Paul left for us to remind us of the spectacular transfer of believers from this world to glorious presence of Christ. Let’s just make sure we are rapture ready and let’s encourage those around us to be ready as well! Like the men on Elephant Island we should be packed and ready to go. The “Boss” may come today.