I John 2:3-4, “And hereby we do know that we know him if we keep his commandments. He that saith I know him and keepeth not his commandments is a liar and the truth is not in him.”.
I John 2:22-23, “Who is a liar but he that denieth that Jesus is the Christ? He is antichrist that denieth the Father and the Son. Whosoever denieth the son the same hath not the Father: but he that acknowleth the Son hath the Father also.”
I john 4:1, “Beloved believe not every spirit but try the spirits whether they are of God: because many false prophets are gone out into the world.”