John 16:5-9

But now I go unto him that sent me; and none of you asketh me, Whither goest thou? But because I have spoken these things unto you, sorrow hath filled your heart. Nevertheless I tell you the truth: It is expedient for you that I go away; for if I go not away, the Comforter will not come unto you; but if I go, I will send him unto you. And he, when he is come, will convict the world in respect of sin, and of righteousness, and of judgment: of sin, because they believe not on me