The Holy Spirit is a real person who came to reside within Jesus Christ's true followers after Jesus rose from the dead and ascended to heaven (Acts 2). Jesus told His apostles...

 

"I will ask the Father, and He will give you another Helper, that He may be with you forever; the Spirit of truth, whom the world cannot receive, because it does not behold Him or know Him, but you know Him because He abides with you, and will be in you. I will not leave you as orphans; I will come to you." (John 14:16-18)

 

The Holy Spirit is not a vague, ethereal shadow, nor an impersonal force. He is a person equal in every way with God the Father and God the Son. He is considered to be the third member of the Godhead. Jesus said to His apostles...

 

"All authority has been given to Me in heaven and on earth. Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, teaching them to observe all that I commanded you; and lo, I am with you always, even to the end of the age." (Matt. 28:18-20)

 

God is Father, Son and Holy Spirit. And all the divine attributes ascribed to the Father and the Son are equally ascribed to the Holy Spirit. When a person becomes born again by believing and receiving Jesus Christ (John 1:12-13; John 3:3-21), God resides in that person through the Holy Spirit (1Cor. 3:16). The Holy Spirit has intellect (1Cor. 2:11), emotion (Rom. 15:30), and will (1Cor. 12:11).

A primary role of the Holy Spirit is that He bears "witness" of Jesus Christ (John 15:26, 16:14). He tells people's hearts about the truth of Jesus Christ. The Holy Spirit also acts as a Christian's teacher (1Cor. 2:9-14). He reveals God's will and God's truth to a Christian. 

 

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