In Christ's Farewell Discourse, or the Upper Room Discourse, there in John 14 through 16, Jesus says so many things about the Spirit that clarify exactly who we're speaking of. The personhood of the Spirit is so clear, starting in chapter 14 where he speaks to the Father about sending another. And when there's so much confusion about the personhood of the Spirit, here's a clear text that shows us that God is not modalistic, that he's not just wearing different hats at different times. Jesus is speaking to the second party, the Father — a different person — who then is being asked to send a third person, the person of the Spirit. So, that's a great distinction that allows us to know that when we're talking about the Holy Spirit we're talking about an independent person, although of course, in the doctrine of the Trinity they are ontologically one God. Later in chapter 16 there are so many verbs that are appended to the Spirit that are helpful: the idea that the Spirit is going to declare; he's going to convict; he's going to hear; he's going to speak. When you look at all these verbs connected to the description of the Spirit, we see we're not talking of an impersonal force, we're not talking of something other than an actual bona fide person with an intellect, emotion and will.