It is significant that in this first verse of what may have been Paul's first inspired epistle, he twice identified the Son of God as "the Lord Jesus Christ," thus giving Him the honor and recognition to which He is entitled.
Paul used this "full name" of Christ at least 19 times in the two brief Thessalonian epistles, as he often did also in his other epistles. Likewise James, in his first verse, called himself "a servant of God and of the Lord Jesus Christ" (James 1:1). Jude warned against any who would deny "the only Lord God, and our Lord Jesus Christ" (Jude 4). Peter began his first epistle with "Blessed be the God and Father of our Lord Jesus Christ" (1 Peter 1:3). The apostle John closed the last book of the Bible with the benediction: "The grace of our Lord Jesus Christ be with you all. Amen" (Revelation 22:21).
In the New Testament epistles, He was also frequently called "Jesus Christ," "Christ Jesus," "the Lord Jesus," "the Lord," or simply "Christ." Once He was called "the Lord Christ" (Colossians 3:24). It is significant, however, that He was never called merely by His human name "Jesus" except when the writer was referring strictly to His human incarnation. In the gospels, the name "Jesus" was used very often in relating His words and deeds, but never did His followers address Him as "Jesus." Always when speaking to Him they addressed Him as "Lord" or "Master" (note John 13:13).
Perhaps modern Christians are too careless when they speak or sing of Him or pray to Him using only His human name. As Peter said, "God hath made that same Jesus, whom ye have crucified, both Lord and Christ" (Acts 2:36). He is now our risen and glorified Lord Jesus Christ! HMM