John 3:13, 32-34

And no man hath ascended up to heaven, but he that came down from heaven, even the Son of man which is in heaven.

And what he hath seen and heard, that he testifieth; and no man receiveth his testimony. He that hath received his testimony hath set to his seal that God is true. For he whom God hath sent speaketh the words of God: for God giveth not the Spirit by measure unto him.