This is the 16th part of a series of posts adapted from a paper I presented at a New Covenant Theology think tank in upstate New York in July 2010.
The Holy Spirit is “Christ in you, the hope of glory,” Paul wrote in Colossians 1:27. It is, according to Abraham Kuyper, a “mystical union with Immanuel.”
Our sanctification is achieved by God through our union with Christ. “He who calls you is faithful; he will surely do it” (1 Thess 5:23–24).
The great existence-altering event that happens in our salvation is our union with Christ through His Spirit.
Paul writes in Galatians 2:20: “I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me.”
To the Romans, he writes:
 Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death?  We were buried therefore with him by baptism into death, in order that, just as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.  For if we have been united with him in a death like his, we shall certainly be united with him in a resurrection like his (Rom 6:3–5).