The doctrine of the Trinity is one of the essential doctrines that separates Christianity from the cults. Note that it is a misunderstanding of the nature of God that forms the foundation for most modern "Christian Cults," such as Mormonism, Jehovah's Witnesses, etc. All quotes are from the KJV.
The eternal Father is neither begotten nor
proceeds.
The Son is eternally begotten of the Father
The
Holy Spirit eternally proceeds from the Father and Son
If you understand what is being said, this is one of the most succinct expressions of the nature of the Trinity. The Father is identified as the eternal, self-existent God. The Son is begotten of the Father, and thus partakes of the nature of the Father, including His Godness, eternality, and unity (thus both are without begining and are one). The Holy Spirit is eternally proceeding from the Father and Son declaring their glory and bringing all into subjection to God's will (thus the Spirit can't have a begining and be created, as He too is God).
I will expound on this in a simple five point break-down of the Trinity.
There is only one God and God is only one. There is no implicit Tri-theism in the doctrine of the Trinity, nor is there any inherint contradiction by saying one in essence (being or existence) and three in person. Trinitarians hold tenaciously to the fact that there is only one God, who is revealed in three persons; not a pantheon; not a tripple god (middle eastern belief where a god would appear in one of three forms at different times, like modern Oneness Pentacostals); not a greater god, a lesser god/angel, and an impersonal force; nor any other straw man arguement or perpetrated lie. Read the context of each of these verses and see that they are not speaking of purpose or fellowship but rather of basic existence.
Only one God, He is creator and Lord of all
Deuteronomy 4:35-39 Unto thee it was shewed, that thou mightest know that the LORD he is God; there is none else beside him. Out of heaven he made thee to hear his voice, that he might instruct thee: and upon earth he shewed thee his great fire; and thou heardest his words out of the midst of the fire. And because he loved thy fathers, therefore he chose their seed after them, and brought thee out in his sight with his mighty power out of Egypt; To drive out nations from before thee greater and mightier than thou art, to bring thee in, to give thee their land for an inheritance, as it is this day. Know therefore this day, and consider it in thine heart, that the LORD he is God in heaven above, and upon the earth beneath: there is none else.
Only one God
Deuteronomy 6:4 Hear, O Israel: The LORD our God, the LORD is one.
Only one God
Ephesians 4:4-6 There is one body and one Spirit - just as you were called to one hope when you were called - one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all.
No God before, none after
Isaiah 43:10-12 "You are my witnesses," declares the LORD, and my servant whom I have chosen, so that you may know and believe me and understand that I am he. Before me no god was formed, nor will there be one after me. I, even I, am the LORD, and apart from me there is no savior. I have revealed and saved and proclaimed - I, and not some foreign god among you. You are my witnesses," declares the LORD, "that I am God.
No God beside Him
Isaiah 44:8 Do not tremble, do not be afraid. Did I not proclaim this and foretell it long ago? You are my witnesses. Is there any God besides me? No, there is no other Rock; I know not one."
No God beside Him
Isaiah 64:4 Since ancient times no one has heard, no ear has perceived, no eye has seen any God besides you, who acts on behalf of those who wait for him.
One would not think this would present a problem to anyone who has read even a modicum of the Bible. Read almost anywhere in the Old Testament to see this is true. I have heard some claim that the Father is not the same as God of the Old Testament, so I am providing a sampling of texts in the New Testament that identifies the Father as God.
Prayer directed to Father
Matthew 6:5-15 And when thou prayest, thou shalt not be as the hypocrites are: for they love to pray standing in the synagogues and in the corners of the streets, that they may be seen of men. Verily I say unto you, They have their reward. But thou, when thou prayest, enter into thy closet, and when thou hast shut thy door, pray to thy Father which is in secret; and thy Father which seeth in secret shall reward thee openly. But when ye pray, use not vain repetitions, as the heathen do: for they think that they shall be heard for their much speaking. Be not ye therefore like unto them: for your Father knoweth what things ye have need of, before ye ask him.
After this manner therefore pray ye:
Our Father which art in heaven, Hallowed be thy name. Thy kingdom come. Thy will be done in earth, as it is in heaven. Give us this day our daily bread. And forgive us our debts, as we forgive our debtors. And lead us not into temptation, but deliver us from evil: For thine is the kingdom, and the power, and the glory, for ever. Amen.
For if ye forgive men their trespasses, your heavenly Father will also forgive you: But if ye forgive not men their trespasses, neither will your Father forgive your trespasses.
Father is God
II Corinthians 1:1-4 Paul, an apostle of Jesus Christ by the will of God, and Timothy our brother, unto the church of God which is at Corinth, with all the saints which are in all Achaia: Grace be to you and peace from God our Father, and from the Lord Jesus Christ.
Blessed be God, even the Father of our Lord Jesus Christ, the Father of mercies, and the God of all comfort;Who comforteth us in all our tribulation, that we may be able to comfort them which are in any trouble, by the comfort wherewith we ourselves are comforted of God.
Father is God
Ephesians 1:1-6 Paul, an apostle of Jesus Christ by the will of God, to the saints which are at Ephesus, and to the faithful in Christ Jesus: Grace be to you, and peace, from God our Father, and from the Lord Jesus Christ.
Blessed be the God and Father of our Lord Jesus Christ, who hath blessed us with all spiritual blessings in heavenly places in Christ: According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love: Having predestinated us unto the adoption of children by Jesus Christ to himself, according to the good pleasure of his will, To the praise of the glory of his grace, wherein he hath made us accepted in the beloved.
Father is God
I Peter 1:1-5 Peter, an apostle of Jesus Christ, to the strangers scattered throughout Pontus, Galatia, Cappadocia, Asia, and Bithynia, Elect according to the foreknowledge of God the Father, through sanctification of the Spirit, unto obedience and sprinkling of the blood of Jesus Christ: Grace unto you, and peace, be multiplied.
Blessed be the God and Father of our Lord Jesus Christ, which according to his abundant mercy hath begotten us again unto a lively hope by the resurrection of Jesus Christ from the dead, To an inheritance incorruptible, and undefiled, and that fadeth not away, reserved in heaven for you, Who are kept by the power of God through faith unto salvation ready to be revealed in the last time.
Sadly, many try to claim that Jesus is not God. This is an old heresy, dating back to Arius in the fourth century, and bearing his name (the Arian heresy). This was refuted by Athanasus, though many still cling to it. The Arian heresy is the foundation of the Jehovah's Witnesses. Again read the verses and their context, and see that they are clearly telling us that Jesus is actually God. Jesus is not an angel, not merely a good man, Jesus is God almighty.
Jesus is God
John 1:1-18 In the beginning was the Word, and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made by him; and without him was not any thing made that was made. In him was life; and the life was the light of men.
And the light shineth in darkness; and the darkness comprehended it not. There was a man sent from God, whose name was John. The same came for a witness, to bear witness of the Light, that all men through him might believe. He was not that Light, but was sent to bear witness of that Light. That was the true Light, which lighteth every man that cometh into the world. He was in the world, and the world was made by him, and the world knew him not. He came unto his own, and his own received him not. 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: Which were born, not of blood, nor of the will of the flesh, nor of the will of man, but of 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 bare witness of him, and cried, saying, This was he of whom I spake, He that cometh after me is preferred before me: for he was before me. And of his fulness have all we received, and grace for grace. For the law was given by Moses, but grace and truth came by Jesus Christ. No man hath seen God at any time; the only begotten Son, which is in the bosom of the Father, he hath declared him.
Everything was created by Jesus (includes angels)
Colossians 1:15-23 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. And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all things he might have the preeminence. For it pleased the Father that in him should all fulness dwell; And, having made peace through the blood of his cross, by him to reconcile all things unto himself; by him, I say, whether they be things in earth, or things in heaven. And you, that were sometime alienated and enemies in your mind by wicked works, yet now hath he reconciled In the body of his flesh through death, to present you holy and unblameable and unreproveable in his sight: If ye continue in the faith grounded and settled, and be not moved away from the hope of the gospel, which ye have heard, and which was preached to every creature which is under heaven; whereof I Paul am made a minister;
Jesus greater than angels, and all else
Hebrews 1 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; Being made so much better than the angels, as he hath by inheritance obtained a more excellent name than they.
For unto which of the angels said he at any time, Thou art my Son, this day have I begotten thee? And again, I will be to him a Father, and he shall be to me a Son? And again, when he bringeth in the firstbegotten into the world, he saith, And let all the angels of God worship him. And of the angels he saith, Who maketh his angels spirits, and his ministers a flame of fire. But unto the Son he saith, Thy throne, O God, is for ever and ever: a sceptre of righteousness is the sceptre of thy kingdom. Thou hast loved righteousness, and hated iniquity; therefore God, even thy God, hath anointed thee with the oil of gladness above thy fellows. And, Thou, Lord, in the beginning hast laid the foundation of the earth; and the heavens are the works of thine hands: They shall perish; but thou remainest; and they all shall wax old as doth a garment; And as a vesture shalt thou fold them up, and they shall be changed: but thou art the same, and thy years shall not fail. But to which of the angels said he at any time, Sit on my right hand, until I make thine enemies thy footstool? Are they not all ministering spirits, sent forth to minister for them who shall be heirs of salvation?
Father and Son both Alpha and Omega
Revelation 1 The Revelation of Jesus Christ, which God gave unto him, to shew unto his servants things which must shortly come to pass; and he sent and signified it by his angel unto his servant John: Who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
Blessed is he that readeth, and they that hear the words of this prophecy, and keep those things which are written therein: for the time is at hand. John to the seven churches which are in Asia: Grace be unto you, and peace, from him which is, and which was, and which is to come; and from the seven Spirits which are before his throne; And from Jesus Christ, who is the faithful witness, and the first begotten of the dead, and the prince of the kings of the earth. Unto him that loved us, and washed us from our sins in his own blood, And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen. Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him. Even so, Amen. I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty.
I John, who also am your brother, and companion in tribulation, and in the kingdom and patience of Jesus Christ, was in the isle that is called Patmos, for the word of God, and for the testimony of Jesus Christ. I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet, Saying, I am Alpha and Omega, the first and the last: and, What thou seest, write in a book, and send it unto the seven churches which are in Asia; unto Ephesus, and unto Smyrna, and unto Pergamos, and unto Thyatira, and unto Sardis, and unto Philadelphia, and unto Laodicea. And I turned to see the voice that spake with me. And being turned, I saw seven golden candlesticks; And in the midst of the seven candlesticks one like unto the Son of man, clothed with a garment down to the foot, and girt about the paps with a golden girdle. His head and his hairs were white like wool, as white as snow; and his eyes were as a flame of fire; And his feet like unto fine brass, as if they burned in a furnace; and his voice as the sound of many waters. And he had in his right hand seven stars: and out of his mouth went a sharp twoedged sword: and his countenance was as the sun shineth in his strength. And when I saw him, I fell at his feet as dead. And he laid his right hand upon me, saying unto me, Fear not; I am the first and the last: I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death. Write the things which thou hast seen, and the things which are, and the things which shall be hereafter; The mystery of the seven stars which thou sawest in my right hand, and the seven golden candlesticks. The seven stars are the angels of the seven churches: and the seven candlesticks which thou sawest are the seven churches.
Compare description of Jesus in Revelation to that of God in Ezekiel.
Ezekiel 1:26-28 And above the firmament that was over their heads was the likeness of a throne, as the appearance of a sapphire stone: and upon the likeness of the throne was the likeness as the appearance of a man above upon it. And I saw as the colour of amber, as the appearance of fire round about within it, from the appearance of his loins even upward, and from the appearance of his loins even downward, I saw as it were the appearance of fire, and it had brightness round about. As the appearance of the bow that is in the cloud in the day of rain, so was the appearance of the brightness round about. This was the appearance of the likeness of the glory of the LORD. And when I saw it, I fell upon my face, and I heard a voice of one that spake.
Jesus is God and equal with Father, voluntarily submits
Philipians 2:5-11 Let this mind be in you, which was also in Christ Jesus: Who, being in the form of God, thought it not robbery to be equal with God: But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men: And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross. Wherefore God also hath highly exalted him, and given him a name which is above every name: That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth; And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father.
It never ceases to amaze me how so many who claim to be Christian, also think the Holy Spirit is an impersonal force rather than God. The Holy Spirit has intellect and will, He is not the Christian version of "the Force" from Star Wars. This has some how integrated into most people's speach who us "it" to refer to the Spirit instead of the proper "He". Show Him the respect He deserves, He is almighty God! Read a few of the quotes below. Note the Holy Spirit is clearly identified as both personal and Devine. For instance, how can a force counsel or be lied to?
Comforter, teaches, causes to remember
John 14:25-27 These things have I spoken unto you, being yet present with you. 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. Peace I leave with you, my peace I give unto you: not as the world giveth, give I unto you. Let not your heart be troubled, neither let it be afraid.
Spirit is God, and personal
Acts 5:1-11 But a certain man named Ananias, with Sapphira his wife, sold a possession, And kept back part of the price, his wife also being privy to it, and brought a certain part, and laid it at the apostles' feet. 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. And Ananias hearing these words fell down, and gave up the ghost: and great fear came on all them that heard these things. And the young men arose, wound him up, and carried him out, and buried him. And it was about the space of three hours after, when his wife, not knowing what was done, came in. And Peter answered unto her, Tell me whether ye sold the land for so much? And she said, Yea, for so much. Then Peter said unto her, How is it that ye have agreed together to tempt the Spirit of the Lord? behold, the feet of them which have buried thy husband are at the door, and shall carry thee out. Then fell she down straightway at his feet, and yielded up the ghost: and the young men came in, and found her dead, and, carrying her forth, buried her by her husband. And great fear came upon all the church, and upon as many as heard these things.
Spirit ministers and is the Lord
II Corinthians 3 Do we begin again to commend ourselves? or need we, as some others, epistles of commendation to you, or letters of commendation from you? Ye are our epistle written in our hearts, known and read of all men: Forasmuch as ye are manifestly declared to be the epistle of Christ ministered by us, written not with ink, but with the Spirit of the living God; not in tables of stone, but in fleshy tables of the heart. And such trust have we through Christ to God-ward: Not that we are sufficient of ourselves to think any thing as of ourselves; but our sufficiency is of God; Who also hath made us able ministers of the new testament; not of the letter, but of the spirit: for the letter killeth, but the spirit giveth life. But if the ministration of death, written and engraven in stones, was glorious, so that the children of Israel could not stedfastly behold the face of Moses for the glory of his countenance; which glory was to be done away: How shall not the ministration of the spirit be rather glorious? For if the ministration of condemnation be glory, much more doth the ministration of righteousness exceed in glory. For even that which was made glorious had no glory in this respect, by reason of the glory that excelleth. For if that which is done away was glorious, much more that which remaineth is glorious. Seeing then that we have such hope, we use great plainness of speech: And not as Moses, which put a vail over his face, that the children of Israel could not stedfastly look to the end of that which is abolished: But their minds were blinded: for until this day remaineth the same vail untaken away in the reading of the old testament; which vail is done away in Christ. But even unto this day, when Moses is read, the vail is upon their heart. Nevertheless when it shall turn to the Lord, the vail shall be taken away. Now the Lord is that Spirit: and where the Spirit of the Lord is, there is liberty. But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord.
Spirit speaks, gives scripture (act of God)
I Timothy 4:1-5 Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils; Speaking lies in hypocrisy; having their conscience seared with a hot iron; Forbidding to marry, and commanding to abstain from meats, which God hath created to be received with thanksgiving of them which believe and know the truth. For every creature of God is good, and nothing to be refused, if it be received with thanksgiving: For it is sanctified by the word of God and prayer.
Spirit is synonymous with God
Psalms 139 To the chief Musician, A Psalm of David.
O LORD, thou hast searched me, and known me. Thou knowest my downsitting and mine uprising, thou understandest my thought afar off. Thou compassest my path and my lying down, and art acquainted with all my ways. For there is not a word in my tongue, but, lo, O LORD, thou knowest it altogether. Thou hast beset me behind and before, and laid thine hand upon me. Such knowledge is too wonderful for me; it is high, I cannot attain unto it. Whither shall I go from thy spirit? or whither shall I flee from thy presence? If I ascend up into heaven, thou art there: if I make my bed in hell, behold, thou art there. If I take the wings of the morning, and dwell in the uttermost parts of the sea; Even there shall thy hand lead me, and thy right hand shall hold me. If I say, Surely the darkness shall cover me; even the night shall be light about me. Yea, the darkness hideth not from thee; but the night shineth as the day: the darkness and the light are both alike to thee. For thou hast possessed my reins: thou hast covered me in my mother's womb. I will praise thee; for I am fearfully and wonderfully made: marvellous are thy works; and that my soul knoweth right well. My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth. Thine eyes did see my substance, yet being unperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them. How precious also are thy thoughts unto me, O God! how great is the sum of them! If I should count them, they are more in number than the sand: when I awake, I am still with thee. Surely thou wilt slay the wicked, O God: depart from me therefore, ye bloody men. For they speak against thee wickedly, and thine enemies take thy name in vain. Do not I hate them, O LORD, that hate thee? and am not I grieved with those that rise up against thee? I hate them with perfect hatred: I count them mine enemies. Search me, O God, and know my heart: try me, and know my thoughts: And see if there be any wicked way in me, and lead me in the way everlasting.
Some take the first four points, and deny the fifth, getting the nonsense of the Oneness movement. The basic idea of Oneness is that god is like a one actor play: (I refuse to capitalize this false god) god comes out as the father in the Old Testament, then he goes off stage and comes back as the son durring the incarnation, then he goes off once more and comes back as the spirit. This is foolishness. To see that it makes no sense, read the following verses and see that the Son prays to the Father, the Father sends the Son, the Son sends the Spirit, the Spirit descends on the Son, all are mentioned in the Great Commision, Father gives things to the Son, etc. These would make no sense if there was no distinction in person (relations, intellect, will) though without distiction in essence. This point is vital. Meaningful interaction can occur between the members of the Trinity without implying that They are not one in their being (existence or essence).
Father sends, Spirit overshadows, Son born
(start
of incarnation not start of Son)
Luke 1:26-38 And in the sixth month the angel Gabriel was sent from God unto a city of Galilee, named Nazareth, To a virgin espoused to a man whose name was Joseph, of the house of David; and the virgin's name was Mary. And the angel came in unto her, and said, Hail, thou that art highly favoured, the Lord is with thee: blessed art thou among women. And when she saw him, she was troubled at his saying, and cast in her mind what manner of salutation this should be. And the angel said unto her, Fear not, Mary: for thou hast found favour with God. And, behold, thou shalt conceive in thy womb, and bring forth a son, and shalt call his name JESUS. He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David: And he shall reign over the house of Jacob for ever; and of his kingdom there shall be no end. Then said Mary unto the angel, How shall this be, seeing I know not a man? And the angel answered and said unto her, The Holy Ghost shall come upon thee, and the power of the Highest shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the Son of God. And, behold, thy cousin Elisabeth, she hath also conceived a son in her old age: and this is the sixth month with her, who was called barren. For with God nothing shall be impossible. And Mary said, Behold the handmaid of the Lord; be it unto me according to thy word. And the angel departed from her.
Holy Spirit Descends on Son as Father speaks
Luke 3:21-22 Now when all the people were baptized, it came to pass, that Jesus also being baptized, and praying, the heaven was opened, And the Holy Ghost descended in a bodily shape like a dove upon him, and a voice came from heaven, which said, Thou art my beloved Son; in thee I am well pleased.
Baptize in name of all three
Matthew 28:16-20 Then the eleven disciples went away into Galilee, into a mountain where Jesus had appointed them. And when they saw him, they worshipped him: but some doubted. And Jesus came and spake unto them, saying, All power is given unto me in heaven and in earth. Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost: Teaching them to observe all things whatsoever I have commanded you: and, lo, I am with you alway, even unto the end of the world. Amen.
Father greater than Son
(note this is a role not ontological distinction)John 14:28-31 Ye have heard how I said unto you, I go away, and come again unto you. If ye loved me, ye would rejoice, because I said, I go unto the Father: for my Father is greater than I. And now I have told you before it come to pass, that, when it is come to pass, ye might believe. Hereafter I will not talk much with you: for the prince of this world cometh, and hath nothing in me. But that the world may know that I love the Father; and as the Father gave me commandment, even so I do. Arise, let us go hence.
Apostolic blessing contained all three distinctly
IICorinthians 13:14 The grace of the Lord Jesus Christ, and the love of God, and the communion of the Holy Ghost, be with you all. Amen.
Father gives to the Son
Revelation 1:1-2 The Revelation of Jesus Christ, which God gave unto him, to shew unto his servants things which must shortly come to pass; and he sent and signified it by his angel unto his servant John: Who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
We can see several things.
Thus the gods of the Mormons, Jehovah's Witnesses, Oneness, Christadelphians, and most all the other "Christian Cults" are not the God of the Bible. It is not possible to over emphasize how important this doctrine is. Every Christian should be ready to explain and defend it by using Scripture.