God is a Spirit. Only God is Holy. God IS the Holy Spirit.

God is a Spirit.

• God is a Spirit:... John 4:24.

God is almighty and supreme. Everything was created by God as THE Father of everything; otherwise, He is not God.

• One Lord, one faith, one baptism, One God and Father of all, who is above all, and through all,... Ephesians 4:5-6.

Only God is holy, Holy, HOLY (Isaiah 6:3 and Revelation 4:8). In truth, the entire concept of holiness is of and from God as the Father.

Knowing only God is Holy by nature and God is a Spirit (John 4:24), we know God is not only a holy Spirit, He is THE Holy Spirit. 

Never forget, ALL of God IS the one and only Holy Spirit because no other Spirit is Holy, period. 

• There is one body, and one Spirit, even as ye are called in one hope of your calling;... Ephesians 4:4.

God is also love.

• …God is love. 1 John 4:8 and 16.

The God kind of love is clearly different from mankind's love. Love of/from God is holy because the source is naturally holy. Mankind's brand of love cannot be holy because the source is not naturally holy.

In the most literal sense, God gives of Himself in His love because He is literally the best of everything conceivable. Otherwise, He is not God. Therefore, the best gifts are of God and from Himself, as the one and only Holy Spirit.

• If ye then, being evil, know how to give good gifts unto your children: how much more shall your heavenly Father give the Holy Spirit to them that ask him? Luke 11:13.
• If ye then, being evil, know how to give good gifts unto your children, how much more shall your Father which is in heaven give good things to them that ask him? Matthew 7:11.

As a loving Father, explained in the next sections titled "Who is God?", God is THE Father to all who want to be His children, and His children call Him Father. 

• But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name: John 1:12.
• And call no man your father upon the earth: for one is your Father, which is in heaven. Matthew 23:9.

Unlike God, who is a Spirit-THE Holy Spirit, man is carnal and made of flesh from the elements of the earth.

• The first man is of the earth, earthy;... 1 Corinthians 15:47.

We know God is THE Holy Spirit, but WHO is He?

First, we must understand and remember that God reveals Himself to us according to His will, as He decides. His will is the supreme law of existence, including the universe, because He made it. Therefore, ALL of God, His persona in all aspects, are God and each is part of the one and only Holy Spirit throughout time and the universe forever. Ephesians 4:4.

The Holy Spirit is the general term for God, but who is He specifically?

Per His will as a true Father, God has revealed Himself to us in three ways. Again, each of them is, by definition, a Holy Spirit and THE Holy Spirit because God is one Spirit, and each of the three individual presentations (personas) of God is God. Think of an apple pie divided into three large pieces. The whole pie is apple pie, and each piece is apple pie.

The Bible tells us the three revelations of God, the Holy Spirit, as personas and presentations so that we may come to know Him, from both:

1. The perspective of heaven (the personas); and
2. The perspective of earth (the presentations). 

From the perspective of heaven, the Spirit realm ("God in heaven"), 

• For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one. 1 John 5:7.

The Holy Spirit (God) is individually and collectively the Father, the Word, and the Holy Ghost.

From the perspective of earth, the physical realm ("God with us on earth"), the Father said:

• Behold my servant, whom I have chosen; my beloved, in whom my soul is well pleased: I will put my spirit upon him, and he shall shew judgment to the Gentiles. Isaiah 42:1 and Matthew 12:18. 

The Father said He has a servant, a soul, and a spirit (lowercase "s" intended) by which we can know Him on earth. (For now, think of the Father's spirit as truth! You will learn that every man (person) has a spirit.)

(Note: The King James New Testament of the Bible uses both the capital "S" when referring to the Spirit of God as God and lowercase "s" for the spirit (truth) as an element partially comprising a persona (including the Father and every person), respectively. Understanding the context is important, and it's easy if we understand who and what God and man are.) 

Yes.

• And God said, Let us make man in our image, after our likeness: Genesis 1:26.

(The plural reference to "us" acknowledges the fact He regards Himself as a trinity of personas (the Father Himself, His Word, and His Truth); and a trinity of presentations (servant/body, soul, and spirit) for man's recognition of his likeness to Him as explained in detail below.)

Of course, God is eternal. The Father is eternal, His Word is eternal, and His Spirit of Truth (the Holy Ghost) is eternal. Therefore, mankind must also be eternal in some way in order for us to be created in His image and likeness, because He is eternal.

In the image of God, like God, there are three personas of every person. All people have a spirit contained within a living soul and housed within a servant-their body. 

• ...and man became a living soul. Genesis 2:7.
• And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ. 1 Thessalonians 5:23. 

Mankind has a body (his servant), a soul (life in him), and a spirit (truth in him). Therefore, if God created man in His image, God the Father must present Himself on earth, in the physical realm, as having a servant body, a soul, and a spirit like His Word says mankind has for us to know Him. He does!

In the likeness of God, man is eternal. Even though his body on earth is perishable like a piece of fruit. Man's soul is eternal. 

• And fear not them which kill the body, but are not able to kill the soul: but rather fear him which is able to destroy both soul and body in hell. Matthew 10:28.
• He that hath an ear, let him hear what the Spirit saith unto the churches; He that overcometh shall not be hurt of the second death. Revelation 2:11.
• And death and hell were cast into the lake of fire. This is the second death. Revelation 20:14.
• But the fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone: which is the second death. Revelation 21:8.

The soul of every man (person) is the life that is given to him as a possession.

• In your patience possess ye your souls. Luke 21:19.

Thus, each of us is our own god.

• ...Is it not written in your law, I said, Ye are gods? John 10:34.
• I have said, Ye are gods;... Psalm 82:6.

First of all, God the Father wants us to know Him! We do that by learning of Him, and we learn of Him by studying His Word.

Speaking on behalf of the Father, Jesus said:

• Take my yoke upon you, and learn of me; for I am meek and lowly in heart: and ye shall find rest unto your souls. Matthew 11:29.
• It is written in the prophets, And they shall be all taught of God. Every man therefore that hath heard, and hath learned of the Father, cometh unto me. John 6:45.

When we study His Word, and match the three personas of God in heaven (in the Spirit realm) to the three presentations of God here on earth (in the physical human realm), we discover who He is and know He is relatable. He chose the personas and presentations according to His will so that we would know Him if we chose to learn of Him, so let's do that.

"God in heaven" (i.e., the personas of God in the Spirit):

• For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one. 1 John 5:7. 

matched with

"God on earth" (i.e., the presentations of God in the physical earth): 

• Behold my servant, whom I have chosen; my beloved, in whom my soul is well pleased: I will put my spirit upon him, and he shall shew judgment to the Gentiles. Isaiah 42:1 and Matthew 12:18. 

gives us this result:

• The Father = the soul (life) of God. He is THE almighty and great "I am". To us, He exists according to His will because He is God. Thus, we know the soul of God, the Father, as the Father's will because He is God and the Father (creator/originator) of everything. Whatever the Father says is a statement of His will and is or shall become.
• The Word = the servant (body) of the Father. (This is exactly the reason why it is dangerous and foolhardy to change the Word of God to please mankind. In doing so, man displeases the Father.)
• The Holy Ghost = the spirit (truth) of the Father. Not surprisingly, the Father's truth is also called the "Spirit of Truth" because He is absolute truth. The Spirit of Truth (Holy Ghost) bears witness to the Father's Word and evidences the Father's will in power because He is absolutely, prophetically, truthful. He teaches us all things and much more by the Spirit of Truth; see John 14:17, 15:26, 16:13, and 1 John 4:6 for starters.  

(Any modern version of the Bible that changed "Holy Ghost" to "Holy Spirit" hides the Spirit of Truth and confuses. That is not a good idea under any circumstance. Stick with the King James Bible for the purest understanding.) 

Yes. More specifically, the question is: are there scriptures that say the spirit (lower case "s" intended") of the Father is the Spirit of Truth (the Holy Ghost)? Yes.

Reproofs: The books of the New Testament written by Matthew and Mark recount many of the same events. One such event refers to the spirit (will) of the Father as "the Spirit of your Father" (Matthew) and "the Holy Ghost" (Mark).

Compare:

• But when they shall lead you, and deliver you up, take no thought beforehand what ye shall speak, neither do ye premeditate: but whatsoever shall be given you in that hour, that speak ye: for it is not ye that speak, but the Holy Ghost. Mark 13:11.

to

• But when they deliver you up, take no thought how or what ye shall speak: for it shall be given you in that same hour what ye shall speak. For it is not ye that speak, but the Spirit of your Father which speaketh in you. Matthew 10:19-20.

See also, the discussions of Romans chapter 8 and 1 Corinthians chapter 2 in a later section.

Thus, the original disciples and authors of the King James New Testament understood the meaning, significance, and identity of the Holy Ghost as the Spirit of Truth in the context of God, the Father. They also understood the distinction between the term Holy Spirit partially comprised of the Holy Ghost and the Word, which agree together, bearing witness to the Father's will! The same cannot be said of any "version" of the New Testament that is not the King James; beware.

To appreciate who and what Jesus is as the first and only begotten human child of the Father (God), we must know the "nature" of the parents always determines the nature of their offspring. For example, zebras (animals) are born from zebras as animals, sparrows (birds) from sparrows as birds, perch (fish) from perch as fish, and people (humans) from people as humans. Being born of God means being born of the Spirit. Jesus was born a human child (mankind) and the Father's son (Spirit). Jesus is the ONE AND ONLY begotten (human-birthed) son of God the Father!

Recall that every person has a body, soul, and spirit.

1. Jesus received His human body from His human parent, Mary His mother.
2. As a human, Jesus was born a living soul like all of us.
3. From the moment of conception, Jesus's spirit was different from ours. Jesus received His spirit (truth) from God as the "offspring" of the Father. Recall that the Father's Word is His servant as His offspring in the Spirit. The Father placed Himself, personified as His Word, as the spirit (truth) inside of that human named Jesus. The Word in Him is the very reason why Jesus IS the only begotten son of God.

Simply stated, the Word of God IS the spirit (truth) inside the man named Jesus the Christ.

• In the beginning was the Word, and the Word was with God, and the Word was God...And the Word was made flesh, and dwelt among us, (and we beheld his glory, the glory as of the only begotten of the Father,) full of grace and truth. John 1:1 and 1:14.

The phrase "the Word was made flesh" (John 1:14) means the Word (Spirit) was given a flesh suit to dwell within because that which is born of the flesh is flesh and that which is born of the Spirit is spirit, see John 3:6. Therefore,

• Jesus was born of mankind (flesh) and Godkind (Holy Spirit) in one body.
• Jesus is both a son of God and a son of man, and only Jesus can declare that truth everywhere.

Believing in Jesus as the savior and the Word of God the Father gives the believer the power to become a son of God and do the works of God according to the Father's will, like the power inside a seed that grows a great tree.

As the Father gives Himself as the Holy Spirit, Jesus gave Himself so we may become children of God by that same Spirit according to the Father's will.

• But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name: John 1:12.
• But after that the kindness and love of God our Saviour toward man appeared, Not by works of righteousness which we have done, but according to his mercy he saved us, by the washing of regeneration, and renewing of the Holy Ghost;... Titus 3:3-7.

Jesus did many other things too numerous to mention.

• And there are also many other things which Jesus did, the which, if they should be written every one, I suppose that even the world itself could not contain the books that should be written. Amen. John 21:25.

No. Jesus said He did not come to send peace on earth, but a sword (Luke 12:51 and Matthew 10:34 above). 

• ...and the sword of the Spirit, which is the word of God: Ephesians 6:17.

The Word is what divides mankind into two groups. It separates the believers as the saved from the unbelievers who remain the damned.

• For the word of God is quick, and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and is a discerner of the thoughts and intents of the heart. Hebrews 4:12.

Yes, Jesus proved it. The scriptural proof is presented in the Foundations following this one. For now, consider this:

• And Jesus being full of the Holy Ghost returned from Jordan,... Luke 4:1.

The Word and Holy Ghost in us are the means by which we are adopted into the Spirit, the family of God, and do the Father's will. 

The Word and the Holy Ghost live in us when we are born again because we are the "body of Christ". 

• Now ye are the body of Christ, and members in particular. 1 Corinthians 12:27.

The Spirit lives in the born again, and our lives in this world are said to be "in Him." As part of the "body of Christ" today, we are the people who represent Him as His ambassadors in this world. Thus, we must be equipped as He was to do the things He did as He said we would.

• Verily, verily, I say unto you, He that believeth on me, the works that I do shall he do also; and greater works than these shall he do; because I go unto my Father. John 14:12.