God's work through his Holy Spirit has been a constant process throughout history, beginning with creation (Genesis 1.2), further as detailed in the pages of scripture, and still today in gifting and working through the church (Romans 8.9-11). Throughout the Bible the Holy Spirit either softened or hardened God's people in their experience with him (Romans 8.7-8), spoke through the prophets (1 Samuel 12.6), and inspired the writing of scripture (1 Peter 1.21). God gave his Spirit to the church through the promise of the Son, giving it gifts and continuing to work in the hearts and lives of the redeemed (1 Corinthians 12, Ephesians 4).
The Holy Spirit has worked int he past to produce the written scriptures and works today to illuminate the scriptures, enabling human beings to hear, understand, apply, and live the word of God (1 Corinthians 2.10-16). Through this process, the Holy Spirit brings conviction of sin (Psalm 119.12, 18), reveals the righteousness of Christ (John 16.14), and provides motivation for transformation, and desire for righteousness through admonishment and teaching (John 2.27, 14.26, 16.8, Ephesians 1.18). Without the work of the Holy Spirit, all people would be dead in trespasses and sins. Indeed, there is no way to see and believe the truth of the gospel of Christ apart from the work of the Holy Spirit.
At conversion, the believer is baptized in the Holy Spirit (1 Corinthians 12.13). That is, the believer is indwell by the Holy Spirit, who enables the believer to bear spiritual fruit, and make him or her more like Christ (Galatians 5.22-24).
Furthermore, the Holy Spirit gives spiritual gifts to members of the church for the edification of the body (Acts 4.31, Romans 8.14). These gifts serve to build up the church in areas of ministry, service, fellowship, and teaching (1 Corinthians 12). While I do indeed believe that the Holy Spirit gives gifts for the edification of the church, I do not believe that the miraculous gifts (healing, miracles, tongues, etc.) are in effect for today. Rather, I believe these gifts to have been given to the apostles and members of the early church for the propagation and verification of the preaching of the gospel. This is not to say that I believe that miracles, hearings, tongues, etc. have ceased, but that the specific gifting of individuals to perform these acts has ceased. I believe this is the pattern that is observable throughout scripture and especially the New Testament, particularly in the book of Acts.