What Is the Essential Truth About the Holy Spirit?

In this blast from the past, J. Warner talks about the essential Christian claims related to the Holy Spirit. What does the Bible teach about the Holy Spirit? Are there certain non-negotiable essentials that all of us, as Christians, must believe about the Holy Spirit in order to call ourselves Christians? Why does it even matter what we believe about the Holy Spirit? What difference does a proper understanding of the Spirit make in our daily lives as Christians?