1 John 2:18-29 Little children, It is the last time: and as ye have heard that antichrist shall come, even now are there many antichrists; whereby we know that it is the last time.  They went out from us, but they were not of us; for they had been of us, they would no doubt continued with us: but they were out, that they might be made manifest that they were not all of us.  But ye have an unction from the Holy One, and ye know all things. I have not written unto you because ye know not the truth. but because ye know it, and that no lie is of the truth. Who is a liar but he that deneith 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 acknowledgeth the Son hath the Father also. Let that therefore abide in you, which ye have heard from the beginning. If that which ye have heard from the beginning shall remain in you, ye also shall continue in the Son, and in the Father, And this is the promise that he hath promised us, even eternal life. These things have I written unto you concerning them that seduce you. But the anointing which ye have received of him abideth in you, and you need not that any man teach you: but as the same anointing teacheth you of all things, and it the truth, and is no lie, and even as it hath taught you, ye shall abide in him. And now little children, abide in him; that; when he shall apear, we may have confidence, and not be ashamed before him at his coming. If ye know that he is righteous, ye know that every one that doeth righteousness is born of him. 

1 John 4:3 And every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world. 

2 John 1:7 For many deceivers are entered into the world, who confess not that Jesus Christ is come in the flesh. This is a deceiver and an antichrist.