I have much more to say to you, more than you can now bear. But when he, the Spirit of truth, comes, he will guide you into all the truth. He will not speak on his own; he will speak only what he hears, and he will tell you what is yet to come. (John 16:12-13, NIV)

Am I correct that the Spirit of Truth is referring to the Holy Spirit?

If so, what does it mean for the Spirit to speak only of what he hears?

Trinitarians believe that the Holy Spirit is God, and God does whatever he wills to do. So how do they interpret these verses?