Since the beginning of the Church at Pentecost the Spirit’s ministry is involved in the conversion of individuals through their hearing and believing the Word of God. This involves Him giving them a whole new birth, i.e. regeneration. The Holy Spirit then permanently indwells believers during this period of His ministry. By this indwelling He serves as the believer's Helper to instruct, empower, and enable each individual to mature in their relationship with God and be equipped in their work of service for Him.
The Spirit also baptizes the believer thereby identifying them with the death, burial, and resurrection of Jesus Christ. The Spirit also seals the believer in their relationship with God which serves as a guarantee of their salvation.
The other ministry of the Holy Spirit to believers today is His filling, or control, that is manifested by living in obedience to God. This control of the Spirit works through the Word of God to guide, direct, lead, and give discernment for daily godly living.