The holy spirit is not a metaphor, or an idea, or a concept, or a fiction, or just part of your own mind. He is an eternal, immortal spirit being. He is also a creator. Just as much real as you are.
"The Holy Spirit, being a creation of the one Creator, creating with Him and in His likeness or spirit, is eternal and has never changed."
In fact, Jesus tells us that we are part of the Holy Spirit, as much as He is part of us. He shares himself with each of us just as much as we each share ourselves with each other. This does not make him literally "our own self".
"This form is not His reality, which God alone knows along with Christ, His real Son, Who is part of Him."
The holy spirit existed before Jesus accepted atonement and exists forever.
"He has established Jesus as the leader in carrying out His plan."
"The Atonement principle was given to the Holy Spirit long before Jesus set it in motion."
The holy spirit is a bridge across the gap of separation who remains permanently aware of God and permanently aware of your connection to him. He is the answer to separation and the bringer of salvation.
"The Holy Spirit is described as the remaining Communication Link between God and His separated Sons. In order to fulfill this special function the Holy Spirit has assumed a dual function. He knows because He is part of God; He perceives because He was sent to save humanity. He is the great correction principle; the bringer of true perception, the inherent power of the vision of Christ. He is the light in which the forgiven world is perceived; in which the face of Christ alone is seen. He never forgets the Creator or His creation. He never forgets the Son of God. He never forgets you. And He brings the Love of your Father to you in an eternal shining that will never be obliterated because God has put it there."
Jesus further clarifies that the Holy Spirit "abides" in your mind, but this does not mean he is literally you or "your right mind". He is IN your right mind and the right minds of all souls, and yet has his own being or spirit and his own mind. He *represents* your self - that doesn't mean He IS your self. He is alike your self, and alike God. He proves you and your father are one, ie, of like kind. The part of your mind that joins with the whole sonship in "christ" is where He lives.
"The Holy Spirit abides in the part of your mind that is part of the Christ Mind. He represents your Self and your Creator, Who are One. He speaks for God and also for you, being joined with Both. And therefore it is He Who proves Them One."
After the atonement plan is complete, and after resurrection of all sons, Holy Spirit will remain as a permanent real creation of God. His function of perception will disappear and He will remain holy. His return to the formlessness of God does not mean He ceases to exist.
"And you will be with him when time is over and no trace remains of dreams of spite in which you dance to death's thin melody. For in its place the hymn to God is heard a little while. And then the Voice is gone, no longer to take form but to return to the eternal formlessness of God."
"When the Atonement is complete and the whole Sonship is healed, there will be no call to return, but what God creates is eternal. The Holy Spirit will remain with the Sons of God, to bless THEIR creations and keep them in the light of joy."