Who is the liar but he who denies that Jesus is the Christ? This is the Antichrist, he who denies the Father and the Son.

 In this verse we meet the conception of Antichrist. Antichrist is a word which occurs only in John's letters in the New Testament ( 1 John 2:22; 1 John 4:3; 2 John 1:7); but it is the expression of an idea which is as old as religion itself. 