A basic theological question in Christianity is: how is God present to us today? In New Testament times, the answer was pretty easy: God is present to us in Jesus of Nazareth. If you lived back then and you wanted to be near to God, a good bet was to go find this Jesus character and follow him around.
Things, of course, are somewhat different now. Jesus is no longer present on earth the way he was in the Gospels. Indeed, God can often seem completely absent from the world. It is much harder to say with certainty ‘God is here’ or ‘God is there’ than it was when Jesus was wandering around Galilee and eating meals and being born in mangers.
Perhaps anticipating that this would be a problem, the Holy Spirit was sent to be with us in his place (John 16:7). So nowadays when we talk about how we know God, how we experience him, how he is involved in the world from day to day, we are talking first and foremost about the Spirit. The theological term for the doctrine of the Holy Spirit is ‘pneumatology’.
When Christians talk about the Holy Spirit, then, we are usually talking about the ways in which God is present to us today. So, for example, if we say that God makes himself known to us through scripture, we talk about it being inspired by the Spirit. That is, God is present through the Bible insofar as the Spirit speaks to us through it. The same sort of thing has often been said of the sacraments and, one way or another, the church. It is also true of the personal immediacy and guidance associated with Pentecostal and charismatic experience (As these examples indicate, some of the biggest historical disagreements between Christians have been about pneumatology.) Any time Christians talk about the practical and concrete ways the invisible God meets us now, we tend to bring up the Holy Spirit.
For Mockingbird purposes, I think a few further themes associated with the Spirit are of particular interest:
(1) The Spirit creates freedom. ‘Where the Spirit of the Lord is, there is freedom’ (2 Cor. 3:17).
(2) The Spirit gives life, particularly to the dead (Gen. 2:7; Ez. 37:3-6; Rom. 8:11).
(3) The Spirit is present in the experience of judgment upon sin, as well as in suffering and being led into the wilderness (John 16:8; Rom. 8:22-23; Luke 4:1-2). More here.
(4) The Spirit is the source of creativity (Gen. 1:2-3; Ps. 104:30).