It is true that the doctrine of the Holy Spirit receives less attention than other doctrines. Historically, the institutional church looked (and still looks) upon the appeal by the masses to the Spirit as potentially subversive and in need of control. Maybe that’s partly why pneumatology is the “odd-ology” (Fabricius).
“The Spirit of God has various roles, and it is a mistake to magnify one of these over all the others.
The Spirit is active in creation, as is also the Word or Logos.
He is at work in revelation, opening our eyes to the significance of what God has accomplished for us in Jesus Christ.
He is the principal agent in our regeneration by which we are born anew into a life of service and freedom (cf. Ezekiel 36:25-27; John 3:1-15; 2 Corinthians 3:17).
He preserves the people of God and indeed all of humanity from the destroying powers of sin, death and hell.
He convicts people of sin and drives them to Christ for mercy and compassion.
He empowers the people of God to bear witness to Christ and triumph over the principalities of the world.
Together with the other members of the Trinity the Spirit is responsible for the incarnation of God in Jesus Christ.
In addition he plays a unique role in the inspiration or supervision of the writing that bears testimony to God’s saving act in Christ, the writing that now forms the canon of Holy Scripture (2 Timothy 3:16-17; 2 Peter 1:20-21).”
Donald G. Bloesch in his excellent ‘Christian Foundations’ series The Holy Spirit – works and gifts, p.73