I have often heard people say that all they need is the Holy Spirit to teach them. They don't need any man to teach them. The Holy Spirit is our teacher, this is true.
What we often forget is that the same Holy Spirit that lives in us also lives in every other believer and He often teaches us through other people. So, the Holy Spirit is still doing the teaching, just through a different vessel than us.
We are one in the Spirit, and from my own experience I have needed the Spirit to speak to me through different vessels. We have our own unique perspective and experiences in which the Spirit has used to speak to us and reveal truth to us. It's the lens in which we see, and we are all unique in this. The Spirit uses all kinds of circumstances, and people to speak, teach, and confirm things to us. Sometimes we need the lens from which another sees.
Remember, Jesus lives His life though us, as us. It looks like us, but it is Him. He expresses Himself uniquely through how He has designed us in our unique temperament.
There are some days it is hard for me to break through my own old thought patterns. You all know what I'm talking about. No sense pretending. And it is often in those days when the Holy Spirit uses another vessel, but it's Him, to speak to me, teach me, or remind me of whatever it is I need for that moment.
So, remember, the Spirit is doing the teaching in your life, always, but the means in which He does it comes through various vessels and situations.