The Scriptures clearly identify who belongs to Christ—that is, who we might term a true Christian. Notice the apostle Paul's teaching in Romans 8:9: "Now if anyone does not have the Spirit of Christ, he is not His" (emphasis added throughout). The Holy Spirit, then, is an essential aspect of the biblical definition of a Christian. Further, only those who are led by God's Spirit have access to eternal life.

Paul continues in Romans 8:11, "But if the Spirit of Him who raised Jesus from the dead dwells in you, He who raised Christ from the dead will also give life to your mortal bodies through His Spirit [which] dwells in you."

It becomes abundantly clear that the Holy Spirit plays a major role in the lives of Christians. In Romans 8:14 Paul defines the Christian very clearly: "For as many as are led by the Spirit of God, these are sons of God." The Holy Spirit identifies us with Christ (Romans 8:9), it makes immortality possible to human, mortal beings (Romans 8:11), it makes possible an obedient, overcoming Christian life (Romans 8:13), and it truly leads (guides, empowers and motivates) the sons of God. In short, God's Spirit—also called the Spirit of Christ—is what makes one a Christian, a Spirit-led follower of Jesus Christ.

If the Holy Spirit is what defines a Christian and makes one a child of God, it is most vital that we learn and understand more about that Spirit and its role.