A second thing we learn from Jesus' words in John 14:16-18 is that the Holy Spirit is a person. Many people have difficulty fully believing this.
There is the story of a woman who came up to a speaker at a Bible conference. The man had just finished delivering a series of messages on the Holy Spirit. The woman said to him, "Before your messages I never thought of it as a person." Obviously, that woman was still thinking of the Holy Spirit as impersonal, an "it".
Now, to be completely honest, I must admit that this passage we are looking at actually uses the neuter pronoun to refer to the Spirit. In the Greek, Jesus calls the Spirit "it". But what we English readers have to understand is that the Greek language has the gender of the pronoun agree with the gender of the noun as in French and some other languages. We do not have anything quite like it in English. Furthermore, even though this passage refers to the Holy Spirit as "it" there are other passages where the Holy Spirit is clearly referred to as "he". In John 16:7 Jesus says, "Unless I go away, the Counselor will not come to you; but if I go, I will send him to you." Ephesians 4:30 tells us not to grieve the Holy Spirit. We cannot grieve a force. We can only grieve a person.
However, getting back to John 14, we can see even in this passage that the Holy Spirit is personal. If the Holy Spirit is another counselor like Jesus, and if Jesus is a person, then it follows that the Holy Spirit must be a person as well. When we talk about a counselor in everyday life we are always talking about another human person. We cannot receive counsel from a computer, information yes, but not counsel, not wisdom.
Why is it important to recognize that the Holy Spirit is a person? I think it is vital because if the Holy Spirit is merely a power ("May the force be with you!") then we will always be asking the question, "How can I get more of it?" However, if the Holy Spirit is a person then we will start asking the right question which is: "How can the Holy Spirit get more of us?"
C. S. Lewis talks about the Holy Spirit in this way:
What grows out of the joint life of the Father and Son is a real Person, is in fact the Third of the three Persons who are God.
This third Person is called, in technical language, the Holy Ghost or the "spirit" of God. Do not be worried or surprised if you find it (or Him) rather vaguer or more shadowy in your mind than the other two. I think there is a reason why that must be so. In the Christian life you are not usually looking at Him: He is always acting through you. If you think of the Father as something "out there," in front of you, and of the Son as someone standing at your side, helping you to pray, trying to turn you into another son, then you have to think of the third Person as something inside you, or behind you. Perhaps some people might find it easier to begin with the third Person and work backwards. God is love, and that love works through men--especially through the whole community of Christians. But this spirit of love is, from all eternity, a love going on between the Father and Son.
And now, what does it all matter? It matters more than anything else in the world. The whole dance, or drama, or pattern of this three-Personal life is to be played out in each one of us: or (putting it the other way round) each one of us has got to enter that pattern, take his place in that dance. There is no other way to the happiness for which we were made. Good things as well as bad, you know, are caught by a kind of infection. If you want to get warm you must stand near the fire: if you want to be wet you must get into the water. If you want joy, power, peace, eternal life, you must get close to, or even into, the thing that has them. They are not a sort of prize which God could, if He chose, just hand out to anyone. They are a great fountain of energy and beauty spurting up at the very centre of reality. If you are close to it, the spray will wet you: if you are not, you will remain dry. Once a man is united to God, how could he not live forever? (Mere Christianity)