“We often tend to think of the Father as transcendent and far off in heaven; similarly, the Son may seem far removed in history and thus also relatively unknowable. But the Holy Spirit is active within the lives of believers; he is resident within us. He is the particular person of the Trinity through whom the entire Triune Godhead currently works in us.”
― Millard J. Erickson, Christian Theology
"The Spirit is God’s transforming presence in our midst. He was sent in order to continue the work of Jesus through the messianic community—the church. This is precisely why Luke opened the Book of Acts by writing, “In my former book, Theophilus, I wrote about all that Jesus began to do and to teach” (Acts 1:1, emphasis added). The statement “all that Jesus began to do and teach” implies that the Book of Acts was a continuation of Jesus’s own mission—through the Spirit-empowered church. The Spirit is another One, sent to minister and to continue Jesus’s ministry, a ministry of miracles and a ministry of spiritual formation. A ministry of mind-boggling exploits and the ministry of quiet, intimate transformation of heart."
Kennedy, Jeff. Father, Son, and the Other One: Experiencing the Holy Spirit as a Transforming, Empowering Reality in Your Life (pp. 41-42). Charisma House. Kindle Edition.