Read John 15:26-27 and 16:4-15
26 “The Helper will come—the Spirit, who reveals the truth about God and who comes from the Father. I will send him to you from the Father, and he will speak about me. 27And you, too, will speak about me, because you have been with me from the very beginning.
4But I have told you this, so that when the time comes for them to do these things, you will remember that I told you.
“I did not tell you these things at the beginning, for I was with you. 5But now I am going to him who sent me, yet none of you asks me where I am going. 6And now that I have told you, your hearts are full of sadness. 7But I am telling you the truth: it is better for you that I go away, because if I do not go, the Helper will not come to you. But if I do go away, then I will send him to you. 8And when he comes, he will prove to the people of the world that they are wrong about sin and about what is right and about God’s judgement. 9They are wrong about sin, because they do not believe in me; 10they are wrong about what is right, because I am going to the Father and you will not see me any more; 11and they are wrong about judgement, because the ruler of this world has already been judged.
“I have much more to tell you, but now it would be too much for you to bear. 13When, however, the Spirit comes, who reveals the truth about God, he will lead you into all the truth. He will not speak on his own authority, but he will speak of what he hears, and will tell you of things to come. 14He will give me glory, because he will take what I say and tell it to you. 15All that my Father has is mine; that is why I said that the Spirit will take what I give him and tell it to you.
The Spirit will guide you into all truth.