Note: All Scripture quotations found in this article are from the text of the Authorized King James Version of the Bible.
The Father, Son (Word) and Holy Ghost are one in agreement on the record that the Father gives eternal life through His Son.
1 John 5:7 “For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.”
1 John 5:11 "And this is the record, that God hath given to us eternal life, and this life is in his Son."
The Father, Son and Holy Spirit are all active in creation. The "us" and "our" in Genesis 1:25 is a reference to the Trinity.
Genesis 1:26 "And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth."
Colossians 1:15-17 "Who is the image of the invisible God, the firstborn of every creature:  For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him:  And he is before all things, and by him all things consist."
Genesis 1:1-2 "In the beginning God created the heaven and the earth.  And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters."
The Father, Son and Holy Spirit are not one person. The Father and Son are two separate persons. The Father is not the Son. The Son is not the Father. Modalism is false doctrine.
Mark 1:10-11 "And straightway coming up out of the water, he saw the heavens opened, and the Spirit like a dove descending upon him:  And there came a voice from heaven, saying, Thou art my beloved Son, in whom I am well pleased."
John 8:17-18 "It is also written in your law, that the testimony of two men is true.  I am one that bear witness of myself, and the Father that sent me beareth witness of me."
The Father and Son both protect us and keep us eternally secure. Both hold us in their hands and they are two distinct persons. The Father and Son are one in agreement in purpose and works.
John 10:28-30 "And I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand.  My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father's hand.  I and my Father are one."
John 17:11 "And now I am no more in the world, but these are in the world, and I come to thee. Holy Father, keep through thine own name those whom thou hast given me, that they may be one, as we are."
John 17:21-23 "That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us: that the world may believe that thou hast sent me.  And the glory which thou gavest me I have given them; that they may be one, even as we are one:  I in them, and thou in me, that they may be made perfect in one; and that the world may know that thou hast sent me, and hast loved them, as thou hast loved me."
The Father is the one true God.
Ephesians 4:4-6 "There is one body, and one Spirit, even as ye are called in one hope of your calling;  One Lord, one faith, one baptism,  One God and Father of all, who is above all, and through all, and in you all."
Malachi 2:10 "Have we not all one father? hath not one God created us? why do we deal treacherously every man against his brother, by profaning the covenant of our fathers?"
1 Corinthians 8:6 "But to us there is but one God, the Father, of whom are all things, and we in him; and one Lord Jesus Christ, by whom are all things, and we by him."
1 Timothy 2:5 "For there is one God, and one mediator between God and men, the man Christ Jesus;"
John 17:1-3 "These words spake Jesus, and lifted up his eyes to heaven, and said, Father, the hour is come; glorify thy Son, that thy Son also may glorify thee:  As thou hast given him power over all flesh, that he should give eternal life to as many as thou hast given him.  And this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent."
The Father creates all things through Jesus Christ, the Son.
Ephesians 3:9 "And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ:"
Jesus Christ is the only begotten Son of the Father.
John 3:16 "For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life."
1 John 4:9 "In this was manifested the love of God toward us, because that God sent his only begotten Son into the world, that we might live through him."
Jesus was God manifest in the flesh.
1 Timothy 3:16 "And without controversy great is the mystery of godliness: God was manifest in the flesh, justified in the Spirit, seen of angels, preached unto the Gentiles, believed on in the world, received up into glory."
The Father was declared by the Son.
John 1:18 "No man hath seen God at any time; the only begotten Son, which is in the bosom of the Father, he hath declared him."
Jesus is the Word. The Word was God.
John 1:1,14 "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."
Jesus is God with us.
Matthew 1:23 "Behold, a virgin shall be with child, and shall bring forth a son, and they shall call his name Emmanuel, which being interpreted is, God with us."
Isaiah 7:14 "Therefore the Lord himself shall give you a sign; Behold, a virgin shall conceive, and bear a son, and shall call his name Immanuel."
The Son is God. The Son is the image of the Father and the brightness of God's glory.
Colossians 1:15 "Who is the image of the invisible God, the firstborn of every creature:"
Hebrews 1:1-3 "God, who at sundry times and in divers manners spake in time past unto the fathers by the prophets,  Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;  Who being the brightness of his glory, and the express image of his person, and upholding all things by the word of his power, when he had by himself purged our sins, sat down on the right hand of the Majesty on high;"
The Son has the fullness of the Father's divine essence.
Colossians 2:9 "For in him dwelleth all the fulness of the Godhead bodily."
Colossians 1:19 "For it pleased the Father that in him should all fulness dwell;"
The Son was sent by the Father and does the Father's will.
John 5:30 "I can of mine own self do nothing: as I hear, I judge: and my judgment is just; because I seek not mine own will, but the will of the Father which hath sent me."
John 4:34 "Jesus saith unto them, My meat is to do the will of him that sent me, and to finish his work."
John 6:38 "For I came down from heaven, not to do mine own will, but the will of him that sent me."
The Son comes in the Father's name.
John 5:43 "I am come in my Father's name, and ye receive me not: if another shall come in his own name, him ye will receive."
John 10:25 "Jesus answered them, I told you, and ye believed not: the works that I do in my Father's name, they bear witness of me."
Everything the Son has comes from the Father.
Matthew 11:27 "All things are delivered unto me of my Father: and no man knoweth the Son, but the Father; neither knoweth any man the Father, save the Son, and he to whomsoever the Son will reveal him."
John 3:35 "The Father loveth the Son, and hath given all things into his hand."
Jesus did miracles through the Holy Ghost and by the power of the Father.
Acts 10:37-38 "That word, I say, ye know, which was published throughout all Judaea, and began from Galilee, after the baptism which John preached;  How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him."
Jesus is given the title "the everlasting Father" because He will forever be a father to Israel in the Millennium. Everlasting Father is a title and Isaiah 9:6 does not mean that the Son is the Father.
Isaiah 22:21 "And I will clothe him with thy robe, and strengthen him with thy girdle, and I will commit thy government into his hand: and he shall be a father to the inhabitants of Jerusalem, and to the house of Judah."
Isaiah 9:6 "For unto us a child is born, unto us a son is given: and the government shall be upon his shoulder: and his name shall be called Wonderful, Counsellor, The mighty God, The everlasting Father, The Prince of Peace."
He that sees Jesus sees the Father because Jesus represents the Father as His image (2 Corinthians 4:4), not that the Son is the Father himself. Jesus is in the Father and the Father in Jesus, the same way we are in God and God is in us, by our fellowship with God. Not because we are God the Father too.
John 14:8-10 "Philip saith unto him, Lord, shew us the Father, and it sufficeth us.  Jesus saith unto him, Have I been so long time with you, and yet hast thou not known me, Philip? he that hath seen me hath seen the Father; and how sayest thou then, Shew us the Father?  Believest thou not that I am in the Father, and the Father in me? the words that I speak unto you I speak not of myself: but the Father that dwelleth in me, he doeth the works."
1 John 4:15-16 "Whosoever shall confess that Jesus is the Son of God, God dwelleth in him, and he in God.  And we have known and believed the love that God hath to us. God is love; and he that dwelleth in love dwelleth in God, and God in him."
The Holy Spirit is the Father's breath, therefore the Holy Spirit is God. The Father's spirit is the Holy Spirit.
Job 33:4 "The Spirit of God hath made me, and the breath of the Almighty hath given me life."
John 20:22 "And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost:"
Acts 5:3-4 "But Peter said, Ananias, why hath Satan filled thine heart to lie to the Holy Ghost, and to keep back part of the price of the land?  Whiles it remained, was it not thine own? and after it was sold, was it not in thine own power? why hast thou conceived this thing in thine heart? thou hast not lied unto men, but unto God."
Matthew 10:20 "For it is not ye that speak, but the Spirit of your Father which speaketh in you."
The Holy Spirit comes in the name of Christ. The Holy Spirit is not Christ.
Romans 8:9-10 "But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.  And if Christ be in you, the body is dead because of sin; but the Spirit is life because of righteousness."
John 14:26 "But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you."
Although the body, soul, and spirit of man may be a type of the Trinity, God is not literally a body, soul, and spirit. That would make God only one person like we are, which is a type Modalistic Partialism.
Jesus' soul prayed to the Father, thus His soul was not the Father.
John 12:27 "Now is my soul troubled; and what shall I say? Father, save me from this hour: but for this cause came I unto this hour."
Jesus had the Holy Ghost inside him, but also had his own spirit because He was a man. As Christians, we did not lose our spirit when we received the Holy Spirit when we trusted Jesus Christ as Saviour.
Luke 23:46 "And when Jesus had cried with a loud voice, he said, Father, into thy hands I commend my spirit: and having said thus, he gave up the ghost."
Jesus' spirit is His own human spirit, not the Holy Spirit. Jesus' spirit called God his Father, but God is never called the Father of the Holy Ghost.
Luke 10:21-22 "In that hour Jesus rejoiced in spirit, and said, I thank thee, O Father, Lord of heaven and earth, that thou hast hid these things from the wise and prudent, and hast revealed them unto babes: even so, Father; for so it seemed good in thy sight. 22 All things are delivered to me of my Father: and no man knoweth who the Son is, but the Father; and who the Father is, but the Son, and he to whom the Son will reveal him."
If Jesus did not have his own human body and spirit like Adam (Genesis 2:7), then he couldn't be "the last Adam" (1 Corinthians 15:45).
Jesus is not the body of the Father. If Jesus is the Father's body, why is the Father outside of Jesus' body on his side?
Acts 7:55-56 "But he, being full of the Holy Ghost, looked up stedfastly into heaven, and saw the glory of God, and Jesus standing on the right hand of God,  And said, Behold, I see the heavens opened, and the Son of man standing on the right hand of God."
Some compare the Trinity to three phases of water, but that's really Modalism (one person who can appear in three different forms). Some compare it to three parts of an egg, but that's really Partialism (no part of the egg is the whole egg, so none of the three persons would be fully God). The Bible has to be the final authority on correctly describing the Trinity. There is no perfect type or picture for the Trinity.
In conclusion, the Father is the one true God with the Holy Spirit being His Spirt. The Lord Jesus Christ is the Father's only begotten Son and He is God because He has the fullness of the Father's divine essence, along with the many other reasons included in the article.