1Finally then, brothers, we beg and exhort you in the Lord Jesus, that as you received from us how you ought to walk and to please God, that you abound more and more. 2For you know what instructions we gave you through the Lord Jesus. 3For this is the will of God: your sanctification, that you abstain from sexual immorality, 4that each one of you know how to control his own body in sanctification and honor, 5not in the passion of lust, even as the Gentiles who don’t know God, 6that no one should take advantage of and wrong a brother or sister in this matter; because the Lord is an avenger in all these things, as also we forewarned you and testified. 7For God called us not for uncleanness, but in sanctification. 8Therefore he who rejects this doesn’t reject man, but God, who has also given his Holy Spirit to you.
9But concerning brotherly love, you have no need that one write to you. For you yourselves are taught by God to love one another, 10for indeed you do it toward all the brothers who are in all Macedonia. But we exhort you, brothers, that you abound more and more; 11and that you make it your ambition to lead a quiet life, and to do your own business, and to work with your own hands, even as we instructed you, 12that you may walk properly toward those who are outside, and may have need of nothing.
13But we don’t want you to be ignorant, brothers, concerning those who have fallen asleep, so that you don’t grieve like the rest, who have no hope. 14For if we believe that Jesus died and rose again, even so God will bring with him those who have fallen asleep in Jesus. 15For this we tell you by the word of the Lord, that we who are alive, who are left until the coming of the Lord, will in no way precede those who have fallen asleep. 16For the Lord himself will descend from heaven with a shout, with the voice of the archangel and with God’s trumpet. The dead in Christ will rise first, 17then we who are alive, who are left, will be caught up together with them in the clouds to meet the Lord in the air. So we will be with the Lord forever. 18Therefore comfort one another with these words.
The teaching of Jesus in John 14:1-3 relates to His future return for believers that is discussed by the apostle Paul in 1 Thess 4:13-18. Both passages have much of the same terminology and relate to the coming of the Messiah.
In John 14, after Jesus announces the betrayal of Judas (John 13:21), His soon departure (13:33), and Peter's denial (13:38), understandably the disciples were disheartened. In view of this Jesus assures them that He is going away but that He is coming again to take them to Himself. Jesus' imagery of an engaged man who, according to ancient custom still practiced today in the middle east, upon becoming betrothed, begins to prepare a room (μοναi, monai) in his father's house for him and his future wife. Upon completion, the engaged man would go to marry his bride, have a feast, and then bring his newly-married wife back to the father's house to live in the room he has built. The passage has often been used for speaking of a believer's death and going to be with Jesus, but the text clearly speaks, using this marriage imagery, of the coming of the bridegroom Jesus to receive His bride at the rapture of the church. The use of the word mansion in the KJV has caused considerable confusion in the text, even spawning songs of mansions that we will live in after we go to heaven, yet the text is speaking of our reunion with Jesus, which is far better, after which we will go to a marriage ceremony, after which she will be with Him forever.
Though Paul's teaching on the coming of Jesus to receive His church does not have the imagery of Jesus' words in John 14:1-3 comparing His coming for believers, the similarity of the words between this passage and 1 Thess 14:13-18 would appear to be speaking about the same event. Both passages speak of the believers (John 14:1; 1 Thess 4:14) as being distraught (John 14:1; 1 Thess 4:13). These persons are said to believers in God and in Jesus (John 14:1; 1 Thess 4:14), and receive this teaching of Jesus' return from Jesus Himself (John 14:2; 1 Thess 4:15), when He returns (John 14:3; 1 Thess 4:15). Those for whom Jesus comes are taken (John 14:3; 1 Thess 4:17) are reunited with Him (John 14:3; 1 Thess 4:17) and be where He is (John 14:3; 1 Thess 4:17).
The accounts are not exactly the same, with the account in John being based on a story relating to marriage and the one in 1 Thessalonians being a straightforward doctrinal passage, but the components are speaking of the same event with Jesus.