Here is the famous Scripture from 1 Thessalonians 4:
"But I would not have you to be ignorant, brethren, concerning them which are asleep, that ye sorrow not, even as others which have no hope. For if we believe that Jesus died and rose again, even so them also which sleep in Jesus will God bring with him. 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 4:13-18)
This passage is very commonly used to support pretribulationism but there is absolutely no grounds for it; on the contrary, 1 Thessalonians 4 fits perfectly with the Biblical doctrine of posttribulationism. Observe certain things about this text:
1. It is concerning the dead in Christ, and it is the hope of the resurrection that is the basis of comfort (not the escaping of tribulation).
2. Verse 14 says Christ will bring the dead in Christ with Him. This is not talking about taking them away but rather gathering them to Him when He comes to earth. This is why it is called the COMING of the Lord, because He COMES.
3. The attributes of this event are an exact parallel of the description Jesus gives of His coming in Matthew 24:
-Christ comes from heaven
-in the clouds
-with a shout
-with a trumpet
-the saints are gathered
"And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. And he shall send his angels with a great sound of a trumpet, [and a great voice], and they shall gather together his elect from the four winds, from one end of heaven to the other." (Matthew 24:30-31, "and a great voice" is included in the footnotes)
This is one and the same event. Paul gives no reason for us to believe the rapture takes place before the tribulation, nor anytime other than when Christ Himself signified. At Jesus' glorious return to earth the saints will be gathered together by the angels to meet the Lord in the air as He is descending. Any interpretation other than this goes beyond the text.