2 Thessalonians 2:3-4
(3) Let no one deceive you by any means; for that Day will not come unless the falling away comes first, and the man of sin is revealed, the son of perdition, (4) who opposes and exalts himself above all that is called God or that is worshiped, so that he sits as God in the temple of God, showing himself that he is God.
2 Thessalonians 2:7-12
(7) For the mystery of lawlessness is already at work; only He who now restrains will do so until He is taken out of the way. (8) And then the lawless one will be revealed, whom the Lord will consume with the breath of His mouth and destroy with the brightness of His coming. (9) The coming of the lawless one is according to the working of Satan, with all power, signs, and lying wonders, (10) and with all unrighteous deception among those who perish, because they did not receive the love of the truth, that they might be saved. (11) And for this reason God will send them strong delusion, that they should believe the lie, (12) that they all may be condemned who did not believe the truth but had pleasure in unrighteousness.
New King James Version
"Let us hold fast the confession of our hope without wavering, for He who promised is faithful.