The Holy Spirit is God’s power in action, his active force. (Micah 3:8; Luke 1:35) God sends out His spirit by projecting his energy to any place to accomplish his will.—Psalm 104:30; 139:7.
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, God resides in that person through the Holy Spirit. The Holy Spirit has intellect, emotion, and will.
A primary role of the Holy Spirit is that He bears “witness” of Jesus Christ. He tells people’s hearts about the truth of Jesus Christ. The Holy Spirit also acts as a Christian’s teacher. He reveals God’s will and God’s truth to a Christian. Jesus told His disciples…
“The Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all that I said to you.”
The Holy Spirit was given to live inside those who believe in Jesus, in order to produce God’s character in the life of a believer. In a way that we cannot do on our own, the Holy Spirit will build into our lives love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Rather than trying to be loving, patient, kind, God asks us to rely on Him to produce these qualities in our lives. Thus Christians are told to walk in the Spirit and be filled with the Spirit. And the Holy Spirit empowers Christians to perform ministerial duties that promote spiritual growth among Christians.
The Holy Spirit also performs a function for non-Christians as well. He convicts people’s hearts of God’s truth concerning how sinful we are — needing God’s forgiveness; how righteous Jesus is — He died in our place, for our sins; and God’s eventual judgment of the world and those who do not know Him. The Holy Spirit tugs on our hearts and minds, asking us to repent and turn to God for forgiveness and a new life.