A Christological Pneumatology?

At a blog called "Read Better, Preach Better" I found these thought provoking words on Keeping in step with the Spirit - Christologically :

Do you think Christologically about the the Holy Spirit? Suppose we’re talking about our New Testament freedom, in the Spirit, to learn to live as God intends. What difference does Jesus make to that freedom (over and above the difference made by, e.g. Moses or Isaiah)? Is it just that Jesus made Pentecost possible - and so the Holy Spirit was given after him - and the Spirit makes obedience possible?

If so, your understanding of the Spirit isn’t Christological.

Revival movements - even ones which start well - need to beware of this danger: rightly speaking of the inward moral power of the Holy Spirit, but doing so unchristologically. That way lies the worst sort of legalism. (The Montanists¹ were an early example.)

The antidote? Reflecting more deeply on what it means for us to be in Christ. Through his Spirit, we enter into Christ’s freedom. We participate in Christ’s authority within the created order.

Or, to put it in Paul’s words, we are no longer slaves, but sons.