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. ... 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. 1 Thessalonians 4:15-17
I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ. 1 Thessalonians 5:23
That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand. Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition. 2 Thessalonians 2:2-3
From The Oxford Annotated Bible's introduction to 2 Thessalonians : "First Thessalonians assumes that Christ's coming again is near.... The thrust of 2 Thessalonians is in the opposite direction...."