The doctrine of the Trinity is one of the most important doctrines of the Christian faith. To study the Bible’s teachings on the Trinity gives great insight into the question that is at the center of all our seeking after God: What is God like himself? Here we learn that in himself, in his very being, God exists in the persons of Father, Son, and Holy Spirit, yet he is one God.
We will define the doctrine of the Trinity as follows: God eternally exists as three persons, Father, Son, and Holy Spirit, and each person is fully God, and there is one God.
The word trinity is never found in the Bible, though the idea represented by the word is taught in many places. The word trinity means “tri-unity: or “three-in-oneness.” It is used to summarize the teaching of Scripture that God is three persons yet one God.
Sometimes people think the doctrine of the Trinity is found only in the New Testament, not in the Old. Although the doctrine of the Trinity is not explicitly found in the Old Testament, several passages suggest or even imply that God exists as more than one person.
For instance, according to Genesis 1:26, God said, “Let us make man in our image, after our likeness.” Some has suggested that God is here speaking to angels, but angels did not participate in the creation of man, nor was man created in the image and likeness of angels, so this suggestion is not convincing. In the first chapter of Genesis we have an indication of a plurality of persons in God himself. We are not told how many persons, and we have nothing approaching a complete doctrine of the Trinity, but it is implied that more than one person is involved. The same can be said of Genesis 3:22 (“Behold, the man has become like us, knowing good and evil”), Genesis 11:7 (“Come, let us go down, and there confuse their language”, and in Isaiah 6:8 (“Whom shall I send, and who will go for us?”).
In Psalm 110:1, David says, “The LORD says to my lord: ‘Sit at my right hand until I make your enemies a footstool for your feet’”. Jesus rightly understands that David is referring to two separate persons as “LORD” (Matthew 22:41-46), but who is David’s “LORD” if not God himself? And who could be saying to God, “Sit at my right hand” except someone else who is fully God? From a New Testament perspective, we can paraphrase this verse: God the Father said to God the Son, ‘Sit at my right hand.’” Even without the New Testament teaching on the Trinity, it seems clear that David was aware of the plurality of persons in one God. Jesus, of course, understood this, when he asked the Pharisees for an explanation of this passage, “no one was able to answer him a word, nor from that day did anyone dare to ask him any more questions” (Matthew 22:46).
Isaiah 63:10 say that God’s people “rebelled and grieved his Holy Spirit”, apparently suggesting both that the Holy Spirit is distinct from God himself, and that this Holy Spirit can be “grieved,” suggesting emotional capabilities characteristic of a distinct person.
Evidence is also found in Malachi, when the Lord says, “The Lord whom you seek will suddenly come to his temple; the messenger of the covenant in whom you delight, behold, he is coming, says the LORD of hosts. But who can endure the day of his coming, and who can stand when he appears?” (Malachi 3:1-2). Here again the one speaking “the LORD of hosts”) distinguishes himself from “the Lord whom you seek,” suggesting two separate persons, both of whom can be called “Lord.”
In Isaiah 48:16, the speaker (the servant of the Lord) says, “And now the Lord GOD has sent me and his Spirit. Here the Spirit of the Lord, like the servant of the Lord, has been “send” by the Lord GOD on a particular mission. From a full New Testament perspective (which recognizes Jesus as the Messiah to be the servant of the Lord predicted in Isaiah’s prophecies), Isaiah 48:16 has Trinitarian implications: “And now the Lord GOD has sent me and his Spirit,” if spoken by Jesus the Son of God, refers to all three persons of the Trinity.
When the New Testament opens, we enter into the history of the coming of the Son of God to earth. It is to be expected that this great event would be accompanied by more explicit teaching about the Trinitarian nature of God, and that is in fact what we find.
When Jesus was baptized, “the heavens were opened and he saw the Spirit of God descending like a dove, and alighting on him; and lo, a voice from heaven, saying, ‘This is my beloved Son, with whom I am well pleased’” (Matthew 3:16-17). Here at one moment we have three members of the Trinity performing three distinct activities. God the Father is speaking from heaven; God the Son being baptized and is then spoken to from heaven by God the Father; and God the Holy Spirit is descending from heaven to rest upon and empower Jesus for his ministry.
At the end of Jesus’ earthly ministry, he tells the disciples that they should go “and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit” (Matthew 28:19). The very names “Father” and “Son,” drawn as they are from the family, the most familiar of human institutions, indicate very strongly the distinct personhood of both the Father and the Son. When “the Holy Spirit” is put in the same expression and on the same level as the other two persons, it is hard to avoid the conclusion that the Holy Spirit is also viewed as a person of equal standing with the Father and the Son.
All three persons of the Trinity are mentioned together in the opening sentence of 1 Peter: “According to the foreknowledge of God the Father, by the sanctifying work of the Spirit, that you may obey Jesus Christ and be sprinkled with his blood” (1 Peter 1:2). Also in Jude 20 – 21, we read, “But you, beloved, build yourselves up on your most holy faith; pray in the Holy Spirit; keep yourselves in the love of God; wait for the mercy of our Lord Jesus Christ unto eternal life.”
In one sense the doctrine of the Trinity is a mystery that we will never be able to understand fully. However, we can understand something of its truth by summarizing the teaching of Scripture in three statements:
1) God is three persons.
2) Each person is fully God.
3) There is one God.
The fact that God is three persons means that the Father is not the Son; they are distinct persons. It also means that the Father is not the Holy Spirit, but they are distinct persons. And it means that the Son is not the Holy Spirit.
John 1:1 – 2 tells us: “In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God.” The fact that the “Word” (who is seen to be Christ in verse 9 -18) is “with” God shows distinction from God the Father. In John 17:24, Jesus speaks to God the Father about “my glory, the glory you have given me because you loved me before the creation of the world,” thus showing distinction of persons, sharing of glory, and a relationship of love between the Father and the Son before the world was created.
Also, the Father is not the Holy Spirit, and the Son is not the Holy Spirit. They are distinguished is several verses. Jesus says, “But the Counselor, the Holy Spirit, whom the Father will send in my name, he will teach you all things, and bring to your remembrance all that I have said to you” (John 14:26). The Holy Spirit also prays or “intercedes” for us (Romans 8:27), indicating a distinction between the Holy Spirit and God the Father to whom the intercession is made.
Finally, the fact that the Son is not the Holy Spirit is also indicated in the several Trinitarian passages, such as the Great Commission (Matthew 28:19), and in passages that indicate that Christ went back to heaven and then sent the Holy Spirit to the church. Jesus said, “It is to your advantage that I go away, for if I do not go away, the Counselor will not come to you; but if I go, I will send him to you” (John 16:7). The name counselor or comforter is a term commonly used to speak of a person who helps or gives comfort or counsel to another person or persons, but is used of the Holy Spirit in John’s gospel.
Other personal activities are ascribed to the Holy Spirit, such as teaching (John 14:26), bearing witness (John 15:26 and Romans 8:16), interceding or praying on behalf of others (Romans 8:26 – 27), searching the depths of God (1 Corinthians 2:10), knowing the thoughts of God (1 Corinthians 2:11), willing to distribute some gifts to some and other gifts to others (1 Corinthians 12:11), forbidding or not allowing certain activities (Acts 16:6 – 7), and being grieved by sin in the lives of Christians (Ephesians 4:30).
In addition to the fact that all three persons are distinct, the abundant testimony of Scripture is that each person is fully God as well. First, God the Father is clearly God. This is evident from the first verse of the Bible, where God created the heaven and earth. It is evident through the Old and New Testaments, where God the Father is clearly viewed as sovereign Lord over all, and where Jesus prays to his Father in heaven.
Next, the Son is fully God. John 1:1 – 4 clearly affirms the full deity of Christ:
In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God; all things were made through him, and without him was not anything made that was made. In him was life, and the life was the light of men.
Here Christ is referred to as “the Word,” and John says both that he was “with God” and that he “was God”.
John 20:28 in its context is also a strong proof for the deity of Christ. Thomas had doubted the reports of the other disciples that they had seen Jesus raised from the dead, and he said he would not believe unless he could see the nail prints in Jesus’ hands and place his hand in his wounded side (John 20:25). Then Jesus appeared to the disciples and Thomas was with them. He said to Thomas, “Put your finger here, and see my hands; put out your hand, and place it in my side; do not be faithless, but believing” (John 20:27). In response to this, we read, “Thomas answered him, ‘My Lord and my God!’” (John 20:28).
Other passages speaking of Jesus as fully divine include Hebrews 1:3, where the author says that Christ is the “exact representation” of the nature or being of God – meaning that God the Son exactly duplicated the being or nature of God the Father in every way. Whatever attributes or power God the Father has, God the Son has them as well.
Next, the Holy Spirit is also fully God. Once we understand God the Father and God the Son to be fully God, then the Trinitarian expressions in verses like Matthew 28:19 (“baptizing them in the name of the Father and of the Son and of the Holy Spirit”) assume significance for the doctrine of the Holy Spirit, because they show that the Holy Spirit is classified on an equal level with the Father and the Son. This can be seen if we recognize how unthinkable it would be for Jesus to say something like, “baptizing them in the name of the Father and of the Son and of the archangel Michael”. This would give to a created being a status entirely inappropriate even to an archangel.
In Acts 5:3 – 4, Peter asks Ananias, “Why has Satan filled your heart to lie to the Holy Spirit…? You have not lied to men but to God.” According to Peter’s words, to lie to the Holy Spirit is to lie to God. Paul says in 1 Corinthians 3:16, “Do you not know that you are God’s temple and that God’s Spirit dwells in you?” God’s temple is the place where God himself dwells, which Paul explains by the fact that “God’s Spirit” dwells in it, thus apparently equating God’s Spirit with God himself.
Paul attributes the divine characteristic of omniscience to the Holy Spirit in 1 Corinthians 2:10 – 11: “For the Spirit searches everything, even the depths of God. For what person knows a man’s thoughts except the spirit of the man which is in him? So also no one comprehends the thought of God except the Spirit of God.”
At this point we have two conclusions, both abundantly taught throughout the Scripture:
1) God is three persons.
2) Each person is fully God.
If the Bible taught only these two facts, there would be no logical problem at all in fitting them together, for the obvious solution would be that there are three Gods. The Father is fully God, the Son is fully God, and the Holy Spirit is fully God. We would have a system where there are three equally divine beings. Such a system of belief would be called polytheism or, more specifically, “tritheism,” or belief in three Gods. But that is far from what the Bible teaches.
Scripture is abundantly clear that there is one and only one God. The three different persons of the Trinity are not only in purpose and in agreement on what they think, but they are one in essence, one in their essential nature. In other words, God is only one being. There are not three Gods. There is only one God.
When God speaks, he repeatedly makes it clear that he is the only true God; the idea that there are three Gods to be worshiped rather than one would be unthinkable. God alone is the one true God and there is no one like him. When he speaks, he alone is speaking, he is not speaking as one God among three who are to be worshipped. He says:
“I am the LORD, and there is no other, besides me there is no God; I gird you, though you do not know me, that men may know, from the rising of the sun and from the west, that there is none besides me; I am the LORD, and there is no other” (Isaiah 45:5 – 6).
The New Testament also affirms that there is one God. Paul writes, “For there is one God, and there is one mediator between God and men, the man Christ Jesus” (1 Timothy 2:5). Paul also affirms that God is one (Romans 3:30), and that “there is one God, the Father, from whom are all things and for whom we exist” (1 Corinthians 8:6). Finally James acknowledges that even the demons recognize that there is one God, even though their intellectual assent to that fact is not enough to save them: “You believe that God is one; you do well. Even the demons believe and shudder” (James 2:19). Clearly James affirms that one “does well” to believe that “God is one”.
We now have three statements, all of which are taught in Scripture:
1) God is three persons.
2) Each person is fully God.
3) There is one God.
Throughout the history of the church there have been attempts to come up with a simple solution to the doctrine of the Trinity by denying one or another of these statements. If someone denies the first statement, then we are simply left with the fact that each of the persons named in Scripture (Father, Son, and Holy Spirit) is God, and there is one God. But if we do not have to say that they are distinct persons, then there is an easy solution: these are just different names for one person who acts differently at different time. Sometimes this person calls himself Father, sometimes he calls himself Son, and sometimes he calls himself Spirit. We have no difficulty in understanding that, for in our own experience the same person can act one time as a lawyer (for example), at another time as a father to his own children, and at another time as a son with respect to his parents: The same person is a lawyer, a father and a son. But such a solution would deny the fact that the three persons are distinct individuals, that God the Father sends God the Son into the world, that the Son prays to the Father, and that the Holy Spirit intercedes before the Father for us.
Another simple solution might be found in by denying the second statement that is, denying that some of the persons named in Scripture are really fully God. If we simply hold that God is three persons, and that there is one God, then we might be tempted to say that some of the “persons” in this one God are not fully god, but are subordinate or created parts of God. This solution would be taken, for example, by those who deny the full deity of the Son (and of the Holy Spirit). But, as we saw above, this solution would have to deny an entire category of Biblical teaching.
Finally, as we noted above, a simple solution could come by denying that there is one God. But this would result in a belief in three God’s, something clearly contrary to Scripture.
When the universe was created God the Father spoke the powerful creative words that brought it into being. God the Son was the divine agent who carried out these words, and God the Holy Spirit was active “moving over the face of the waters”. So it is as we would expect: if all three members of the Trinity are equally and fully divine, then they have all existed for all eternity and God has existed as a Trinity. God cannot be other than he is, for he is unchanging. Therefore it seems right to conclude that God necessarily exists as a Trinity, he cannot be other than he is.