'Anti christ' in the Bible

Dear children, the last hour has come; and as you once heard that there was to be an anti-Christ, so even now many anti-Christs have appeared. By this we may know that the last hour has come.

Who is a liar compared with him who denies that Jesus is the Christ? He who disowns the Father and the Son is the anti-Christ.

and that no spirit is from God which does not acknowledge this about Jesus. Such is the spirit of the anti-Christ; of whose coming you have heard, and it is already in the world.