2Thessalonians 2:3-4 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; Who opposes and exalts himself above all that is called God, or that is worshipped; so that he as God sits in the temple of God, showing himself that he is God.
Two events precede the Day of the Lord (continues): The great whore of Revelation 17:1-18 will destroy multitudes of Christians during the first 3½ years of Daniel’s 70th week, while the Antichrist is coming to power over the 10 kingdoms inside the old Roman Empire (Rev. 6:9-11; 17:6). When the Antichrist comes to full power over the 10 kingdoms in the middle of Daniel’s 70th week, he, together with the 10 kings, will destroy the great whore, establish the worship of the beast, and kill multitudes who will not worship him and his image or take his brands (Rev. 7:9-17; 13:1-18; 14:9-13; 15:2-4; 16:6-11; 17:2-4, 16-17).  The man of sin is revealed (2:3).
‘The son of perdition’ – Used for the Antichrist (2:3), and in the Septuagint of children of transgression (Isa. 57:4). Hebrews and Greeks called anyone who had a particular destiny, quality, or trait, the child of that thing, as “children of the kingdom” (Matt. 8:12; 13:38); “of the bridechamber” (Matt. 9:15); “of hell” (Matt. 23:15); “of wrath” (Eph. 2:3); “of wisdom” (Matt. 11:19; Luke 7:35); etc. Judas (John 17:12) and the Antichrist have no relationship with each other as to parents, birth, life, death, etc. Both are simply destined for destruction by their own deeds. The Antichrist will die at the hands of Christ, while Judas hung himself (2:8; Dan. 7:11; Isa. 11:4; Rev. 19:20).
‘Worshipped’ – This refers to the beast worship of Revelation 13:1-18; 14:9-11; 15:2-4; 16:2-12; 19:20; Daniel 9:27; 11:35-45; 12:7 and Matthew 24:15.