This is widely claimed as the central doctrine of Christianity. It teaches that there are three distinct persons in one God; God the Father, God the Son and God the Holy Spirit. What then is the basis of this doctrine? Is this teaching of three persons in one God taught in both Old and New Testament Scriptures?
Before considering these questions there are some important things I need to clarify to avoid misrepresentation of the doctrine of the trinity.
First, Trinitarianism is not a teaching of three “separate” persons in the Godhead. A Dictionary of Theological Terms (by M.E. Manton) says, “… The persons of the trinity are not separate, but they are distinct from each other.” Second, Trinitarianism is not tri-theism (the existence of three separate gods). Third, a person does not necessarily mean a physical body. Fourth, the word “God” in Scripture sometimes is expressive of divine nature or essence, and sometimes of one of the persons in that nature or essence.
More on the terms, “God” and “person.” When Christ said, “I and my Father are one” (John 10:30), He signified one in nature or essence, not in person. This was understood by the Jews. With anger they said, “… Thou being a man, makest thyself God” (v. 33). In verse 36, Jesus told them that He was the Son of God, and this referred to His deity. He meant He is one with the Father in the divine nature. What do we mean by a person? “A person, is an individual who subsists and lives of himself, endowed with will and understanding. Such is the Father, therefore a person; such is the Son, therefore a person; such is the Holy Spirit, therefore a person” (A. W. Pink). The divine persons are distinct from each other, but one in nature or essence.
The Holy Scripture is the basis of the doctrine of the divine trinity. This is clearly taught in both Old and New Testament Scriptures. The one living and true God has revealed Himself to men in three distinct persons as the Father, the Son and the Holy Spirit in His inspired Word. The student of the Word can find this glorious truth as definitely and as frequently taught in the New Testament as in the Old Testament.
I. The Plural Pronouns In The Scriptures Pointing To The Divine Persons As Antecedents Are Apparent Proofs That The Trinity Doctrine Is Scriptural.
“And God said, Let US make man in OUR image…. “(Genesis 1:26). These pronouns reveal the fact that there is more than one person in the Godhead! God, in Genesis 1:26, was not talking to an angel. The statement in Luke 1:19 which says, “And the angel answering said unto him, I am Gabriel, that stand in the presence of God;…”, is not an apparent or reasonable indication that angels were already present with God in eternity, before the foundation of the world, when God decreed the creation of man in time. Moses wrote what God had revealed to him. God’s statement in Genesis 1:26 was not simply stated by God Himself, originating in the same week when God said, “Let there be light…” (Genesis 1:3). The statement in Genesis 1:26 is also an eternal decree of God. He made this decree in eternity, before the foundation of the world, when there was no angel yet existing as God’s creature. Let it be borne in mind, that the record of God’s words in Genesis 1:26 is but an open transcript of what he said before the creation of heaven and earth “when no one was yet created.” In this statement, “I am Gabriel, that stand in the presence of God,” the verb stand, is in the present tense, not past progressive or an action that took place in the indefinite past or an action that took place in the indefinite past and is continuing up to the present.
Genesis 1:26, is not the only passage in the Old Testament where the plural pronouns are used of God. After Adam had fallen, we find God saying, “Behold, the man is became as one of US, to know good and evil” (Genesis 3:22). Still, in the book of Genesis, in response to the impiety of those who had said, “Go to, let us build us a city and a tower whose top may reach unto heavens,” the Lord said, “Go to, let US go down and there confound their language” (Genesis 11:7).
“In that marvelous vision granted unto Isaiah, wherein he saw the Lord seated upon a throne, high and lifted up, and His train filled the Temple; before Whom the seraphim veiled their faces, the prophet heard the voice of the Lord saying, “Whom shall I send, and who will go for “US” (Isaiah 6:8). Very wonderful is that “I” and “US”, intimating the divine unity in trinity, and the trinity in unity” (A. W. Pink).
“Produce your cause, saith the Lord; bring forth your strong reasons, saith the King of Jacob. Let them bring forth, and show US what shall happen let them show the former things, what they be, that WE may consider them, and know the latter end of them; or declare US things for to come” (Isaiah 41:21, 22). “Jesus answered and said unto him, If a man love me, he will keep my words and my Father will love him and WE will come unto him, and make OUR abode with him” John 14:23).
II. The Distinctions Of the Divine Persons In The Godhead Are Made Clear By The Fact That In The Scriptures They Are Frequently Represented As Speaking To One Another.
“I will declare the decree the Lord hath said unto me (not of me), Thou art my Son; this day have I begotten Thee” (Psalm 2:7). The Son of God is heard speaking to the Father, saying “Lo, I come in the volume of the book it is written of Me. I delight to do Thy will, O my God; yea, Thy law is within my heart” (Psalm 40:7-8). In Psalm 45, the Father says to His Son, (The writer of the Psalms clearly declared that God was talking to the Son of God.) “Thy throne, O God, is forever and ever; the scepter of thy kingdom is a right scepter” (v. 6). One more, in Psalm 110, “The Lord said unto my Lord, sit Thou at my right hand, until I make Thine enemies Thy footstool” (v.1) So it is very clear in these verses that God the Son was talking to God the Father, and God the Father was talking to God the Son. This clearly shows that God the Father, and the Son of God are not the same person. The distinction between the Father and the Son is most clearly set forth in these passages of Scriptures.
III. Passages In Both Old Testament And New Testament Where The Three Divine Persons – Father, Son And Holy Spirit – Are All Distinctly Mentioned Together.
In Isaiah 48:16 we read, “Come ye near unto me, hear ye this; I have not spoken in secret from the beginning; from the time it was, there was I; and now the  Lord God, and His  spirit, hath sent  me.
So the  spirit took me up and brought me into the inner court; and behold, the glory of the LORD filled the house. And I heard  him speaking unto me out of the house and the  man stood by me” (Ezekiel 43:5-6). While the prophet was adoring the manifest glory of God, the Spirit conducted him into the inner chamber, while beside him stood the One Who had been instructing him – “the man.” See Ezekiel 40:3. This verse says, “And he brought me thither, and behold there was a man, whose appearance was like the appearance of brass, with a line of flax in his hand, and a measuring reed and he stood in the gate.” This man is generally accepted as the Son of God, the Lord Jesus Christ. Thus the prophet had a vision of the three distinct persons m the Godhead, manifesting in different ways their presence with him.
In the New Testament “When the  Comforter is come Whom  I will send unto you from the  Father, even the  Spirit of truth which proceedeth from the  Father, he shall testify of  me” (John 15:26).
“I beseech, you brethren, for the  Lord Jesus Christ’s sake, and for the love of the  Spirit, that ye strive with me in your prayers to  God” (Romans 15:30).
“For through [1 ] him (that is Christ) we both have access by one  spirit unto the  Father” (Ephesians 2:18). “ Christ, who through the eternal  spirit offered himself to  God” (Hebrews 9:4) “Elect according to the foreknowledge of  God the Father, through the sanctification of the  spirit, unto obedience and sprinkling of the blood of  Jesus Christ” (I Peter 1:2). These are just a few of the many, many verses in the Bible where all the three divine persons are distinctly mentioned together.
IV. The Three Distinct Persons Are Clearly Revealed At The Baptism Of Jesus Christ.
“And Jesus when he was baptized, went up straightway out of the water and, lo the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him and, lo, a voice from heaven, saying, This is my beloved son in whom I am well pleased” (Mark 3:16-17). Let it be carefully observed all three persons of the Godhead were present here yet were clearly distinguished from each other, and manifested severally, and that, in such a way and manner as is needed to define the person of each. Here was the person of the Father, manifested by a voice from heaven. Here was the person of the Son, manifested as a man, coming up from the water. Here was the person of the Holy Spirit manifested in the form of a dove, lighting upon the Son. What could more clearly distinguish the eternal three, the Father speaking, the Son spoken of, and the Spirit manifested apart from both!
There are those who have denied the three distinct persons in the Godhead, and teach “only one person in the Godhead.” They claim the demonstrative pronoun “this” and the preposition “in,” in Matthew 3:17 show the Father and the Son are the same and only one person. “… This is my beloved Son in whom I am well pleased.” They say the Father did not use “that” but “this” showing the Father and the Son are the same or one person. According to them the “this” and “in” show that the Father and the Son are not apart and not distinct from each other. According to their explanation, when you say, “This is a chair”, it means you are not apart from or separated from the chair. They are wrong when they use this illustration to teach that God the Father, and the Son of God are the same person. Do they mean the one speaking and the chair are the same or have no distinction? Also, they explained the preposition “in” means the Father is in Christ showing the Father and the Son are the same. No, the preposition “in” does not mean the Father and the Son are the same or have no distinction. The student of the Scripture can easily understand especially if he would compare Scripture with Scripture. For example, there are many Scriptures stating that a believer is “ in” Christ. “…if a man be “in Christ”, he is a new creature” (II Corinthians 5:17). Because of the preposition “in” are the believer and Christ the same person?
I have already pointed out that Trinitarianism does not teach three distinct “separate” persons. It teaches three distinct (unified) persons in the Godhead. The Godhead, meaning the divine nature or essence is only one. In this one divine nature or essence the Father, the Son and the Holy Spirit subsist. The “three divine persons” does not mean that the Godhead is divided, so that the Father is one part of deity! the Son another part, and the Spirit still a third part. “The divine nature or essence is the Godhead, simply and absolutely considered a person is that which subsisteth in the Godhead, as Father, Son and Holy Spirit” (W. Perkins, 1595). It is the divine persons in the union of the divine essence which are to be distinguished, and not the nature or the divine essence of the Godhead.
V. Each Of The Three Divine Persons Existed As A Distinct Person In Eternity.
First, it is generally accepted that God the Father already existed in eternity. There are believers of the preexistence of Christ, who deny that He existed in eternity past, as a distinct person. Of course, they are wrong.
“And now, O Father, glorify thou me with thine own self with the glory which I had with thee before the world was” (John 17:5). The emphasis I make at this point, is not just that the Son is co-equal in glory with the Father? What I mainly point out here is that the Son co-existed with the Father as a distinct person. The verse clearly teaches that Jesus Christ had His glory with the Father, even before the foundation of the world.
“Father, I will that they also, whom thou hast given me, be with me where I am; that they may behold my glory, which thou has given me for thou lovedst me before the foundation of the world” (John 17:24). The one who loved and the one who is loved are clearly distinct from each other thus not the same person. It is very clear that Jesus Christ being loved by the Father was a distinct person in eternity.
What about the Holy Spirit? We can see His role in creation in Genesis 1:2. He is known as the eternal Spirit. “Christ, who through the eternal spirit offered himself to God” (Hebrews 9:24).
Before this is concluded, there are some more facts which need to be considered. First, is tri-theism which has already been mentioned as contrary to the Scriptures. “God’s essence is homogeneous, undivided and indivisible. Composibility and divisibility are both impossible with God. Again, let it be said, this does not preclude the doctrine of the trinity, for trinity refers not to component parts (i.e. Father, Son and Holy Spirit), but to three distinctions of person in the same being” (F. L. Keener).
There is another teaching about God known in history as Sabellianism. The Encyclopedia Britannica, 15th Edition, Vol VIII, Page 747 says, “Sabellianism a Christian Heresy. It was propounded by Sabellius (Flourished C. 217 – C. 220) who was possibly a Presbyter in Rome…Sabellius evidently taught that the Godhead is a monad, expressing itself in three operations as Father, in creation; as Son, in redemption; as Holy Spirit, in sanctification”. Students of the Word can be delivered from this heresy by understanding carefully the distinction of the three divine persons before the incarnation of the Son of God, indeed, even before the foundation of the world. This is because, according to Sabellianism, Father, Son and Holy Ghost are also dispensations of the Godhead, beside that these are also viewed as offices.One of the keys to showing the implausibility of Sabellianism is to point to the distinction of the three divine persons as they are clearly revealed in both the Old and the New Testaments. It is like rapture, demons, hypostatic union and many more theological terms which cannot be found in the Bible, yet they are accepted and very clearly taught.
Articles written against the Trinity by non-Christians, pagans and Unitarians are flooding book stores. They even contribute to my study, as reference books, and are found in our large libraries. Aside from the writers being so biased, it is noticeable that they have not gone to a thorough study of the Holy Scriptures with the Holy Spirit enlightening them. Let it be noted that the trinity is a mystery and cannot be learned except by God’s revelation, the Holy Scriptures.
It has been published that Theophilus coined the word “trinity” (Greek Triad). The origin of trinity was ascribed to Theophilus, the sixth Bishop of Antioch, in 180 A.D. Encyclopedia Britannica, 15th Edition, Vol. IX says, “He (Theophilus) is the earliest writer who mentions the inspiration of the New Testament writings; the triad of God, his word, and his wisdom;…” By this historical information, you can notice how misrepresentation was made by ascribing to Theophilus the origin of the trinity. We only ascribe to the Holy Scriptures the origin of this great doctrine of the trinity.
The three divine persons Who are antecedents of the plural pronouns; the Father talking to the Son, and the Son talking to the Father, even long before the incarnation of Christ; each verse where the three divine persons are distinctly mentioned together; the manifestation of all the three divine persons when Christ was baptized in the Jordan river; and the existence of the Son with the Father in eternity as clearly set forth in John 17:5 and 24 all clearly show us the scripturality of the divine trinity.
“In hope of eternal life, which God, that cannot lie, promised before the world began” (Titus 1:2). The word “promised” here reminds us of the eternal covenant. By one party alone a promise or covenant would be impossible. The undeniable fact here is, in eternity there was a covenant or promise made! My dear reader friend, with whom was this eternal covenant or promise made? It was with and between the three holy persons of the Godhead.