'Liar' in the Bible

If we say that we have not sinned, we make him a liar, and his word is not in us.

He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him.

Who is a liar but he that denieth that Jesus is the Christ? He is antichrist, that denieth the Father and the Son.

If a man say, I love God, and hateth his brother, he is a liar: for he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen?

He that believeth on the Son of God hath the witness in himself: he that believeth not God hath made him a liar; because he believeth not the record that God gave of his Son.