Let's look at 1 Thessalonians 4:16-17 once more.
For this we say unto you by the word of the Lord, that we which are alive and remain unto the coming of the Lord shall not prevent them which are asleep. For the Lord himself shall descend from heaven with a shout, with the voice of the archangel, and with the trump of God: and the dead in Christ shall rise first: Then we which are alive and remain shall be caught up together with them in the clouds, to meet the Lord in the air: and so shall we ever be with the Lord. Wherefore comfort one another with these words.
- 1 Thessalonians 4:15-18 (KJV)
The word "in the clouds" denotes "in a group." In other words, when Jesus arrives, we will assemble as a group with the saints who will accompany Him.
In Hebrews 12:1, Paul alludes to a big cloud of witnesses, which means a collection of witnesses, using the same colloquial term:
Wherefore seeing we also are compassed about with so great a cloud of witnesses, let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us,
- Hebrews 12:1 (KJV)
Christ will stand on the Mount of Olives when He returns. That is where we assemble to worship Him, not in the clouds created of water vapor in the sky.
Now, you’ll need to look up one more term. In verse 17, the term is "air." The Greek term aer, which also means to breathe or respire, is translated as "air." It refers to our spiritual body, which is also known as our "breath of life" body.