The antichrist is also known as ‘the beast’, ‘the man of sin’ and the ‘son of perdition’. He is literally Satan incarnate.
Now, brethren, concerning the coming of our Lord Jesus Christ and our gathering together to Him, we ask you, not to be soon shaken in mind or troubled, either by spirit or by word or by letter, as if from us, as though the day of Christ had come. 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, 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 (NKJV)
Who is a liar but he who denies that Jesus is the Christ? He is antichrist who denies the Father and the Son.
1 John 2:22 (NKJV)
Little children, it is the last hour; and as you have heard that the Antichrist is coming, even now many antichrists have come, by which we know that it is the last hour.
1 John 2:18 (NKJV)
And every spirit that does not confess that Jesus Christ has come in the flesh is not of God. And this is the spirit of the Antichrist, which you have heard was coming, and is now already in the world.
1 John 4:3 (NKJV)
For many deceivers have gone out into the world who do not confess Jesus Christ as coming in the flesh. This is a deceiver and an antichrist.
2 John 1:7 (NKJV)
Then the beast was captured, and with him the false prophet who worked signs in his presence, by which he deceived those who received the mark of the beast and those who worshiped his image. These two were cast alive into the lake of fire burning with brimstone.
Revelation 19:20 (NKJV)