"What, or who is the Holy Spirit? Most Christians readily and warmly respond to the description of Jesus as the Son of God not only because of his humanity (Jesus), but also because the designation 'Son' indicates a relational identity (son-father) with which we are familiar. In addition, when, in Christ, we learn to call God 'Father', that name conveys a rich kaleidoscope of images which helps us to understand and respond to him as the one who governs, guides, provides for, guards and loves his children.
"But the name 'Holy Spirit', or worse (at least at the emotional and psychological levels) 'Holy Ghost', tends to convey a cold, even remote image. After all, what is 'Spirit'? Yet, perhaps the older 'Holy Ghost', with its connotations of vagueness, mystery and insubstantiality, did in fact express what many Christians experience: the Holy Spirit is seen to be distant and impersonal by comparison with the Father and the Son. 'We know not what spirits are, nor what our own spirit is,' wrote Abraham Kuyper. How much less capable are we of comprehending the Spirit of God?
"What, or who, then, is the Holy Spirit?"
-the opening words of chapter 1 of Sinclair Ferguson's excellent book The Holy Spirit
The Lord's Day, June 12, 2011.
Decatur Presbyterian Church.