How Can One God Be Three?

How Can One God Be Three?

Speaking through the prophet Isaiah, God said, “My thoughts are not your thoughts, / Nor are your ways My ways … / For as the heavens are higher than the earth, / So are My ways higher than your ways, / And My thoughts than your thoughts” (Isa. 55:8–9). God is infinite, man is finite, so there are mysteries about God that man cannot fully understand. One of these mysteries is the Trinity, the tri-personality of God. According to Christian orthodoxy, God is one God in essence, power, and authority, and also eternally exists as three distinct co-equal persons. These three persons are the Father, the Son (Jesus), and the Holy Spirit. This does not mean that Christians believe in three gods (polytheism). Rather, the doctrine of the Trinity is that there is only one God who exists in three distinct persons, and all three share the exact same divine nature or essence.

Understanding this fully is beyond human comprehension and has no human parallels, although various analogies have been offered. One of these analogies is the three physical states of water. Water is not only a liquid but also a solid (ice) and a gas (vapor), yet its chemical composition (substance) never changes in all three forms (two parts hydrogen and one part oxygen—H2O). Although such analogies help us visualize the concept of the Trinity, they all fall short in some way. In the case of the water analogy, although the molecule H2O can be liquid, solid, or gas, it is never all three at one time. The Trinity, on the other hand, is all three persons as one God.

The word Trinity is not used in Scripture, but it has been adopted by theologians to summarize the biblical concept of God. Difficult as it is to understand, the Bible explicitly teaches the doctrine of the Trinity, and it deserves to be explained as clearly as possible, especially to non-Christians who find the concept a stumbling-block to belief. So let’s dig into this topic by addressing four key questions.


The doctrine of the Trinity is certainly a mystery but that doesn’t mean it’s irrational. The concept cannot be known by human reason apart from divine revelation, and, as we’ll soon see, the Bible definitely supports the idea of the Trinity. But for now, I want to demonstrate that the doctrine of the Trinity, although beyond human comprehension, is nevertheless rational. Our acceptance of it is congruous with how we respond to other data about the known world.

There are many things about the universe we don’t understand today and yet accept at face value simply because of the preponderance of evidence supporting their existence. The scientific method demands that empirical evidence be accepted whether or not science understands why it exists or how it operates. The scientific method does not require that all data be explained before it is accepted.

Contemporary physics, for instance, has discovered an apparent paradox in the nature of light. Depending on what kind of test one applies (both of them “equally sound”), light appears as either undulatory (wave-like) or corpuscular (particle-like). This is a problem. Light particles have mass, while light waves do not. How can light have mass and not have it, apparently at the same time? Scientists can’t yet explain this phenomenon, but neither do they reject one form of light in favor of the other, nor do they reject that light exists at all. Instead, they accept what they’ve found based on the evidence and press on.

Like physicists, we are no more able to explain the mechanics of the Trinity than they can explain the apparent paradox in the nature of light. In both cases, the evidence is clear that each exists and harbors mystery. So we must simply accept the facts and move on. Just because we cannot explain the Trinity, how it can exist, or how it operates does not mean that the doctrine must be rejected, so long as sufficient evidence exists for its reality. So let’s now explore this evidence.



Although the doctrine of the Trinity is fully revealed in the New Testament, its roots can be found in the Old Testament.

In several places, God refers to Himself in plural terms. For example, “Then God said, ‘Let Us make man in Our image’” (Gen. 1:26; see 3:22; 11:7; Isa. 6:8).

The Messiah was prophesied in the Old Testament as being divine. Isaiah 9:6 states that the Messiah will be called “Mighty God,” a term applied in the Old Testament specifically to Yahweh (see Mic. 5:2).

Isaiah 48:16 refers to all three members of the Godhead: “Come near to Me, listen to this: From the first I have not spoken in secret, from the time it took place, I was there. And now the Lord God [Father] has sent Me [Jesus], and His Spirit [the Holy Spirit]” (nasv).

The Old Testament also makes numerous references to the Holy Spirit in contexts conveying His deity (Gen. 1:2; Neh. 9:20; Ps. 139:7; Isa. 63:10–14).


The New Testament provides the most extensive and clear material on the Trinity. Here are just a few of the texts that mention all three members of the Godhead and imply their co-equal status.

•     Matthew 28:19, the baptismal formula: “Go therefore and make disciples of all the nations, baptizing them in the name [not ‘names’] of the Father and of the Son and of the Holy Spirit.”

•     Matthew 3:16, at the baptism of Christ in the Jordan: “And after being baptized, Jesus went up immediately from the water; and behold, the heavens were opened, and He saw the Spirit [Holy Spirit] of God [Father] descending as a dove, and coming upon Him [Jesus]” (nasv).

•     Luke 1:35, the prophetic announcement to Mary of Jesus’ birth: “And the angel answered and said to her, ‘The Holy Spirit will come upon you, and the power of the Highest [Father] will overshadow you; therefore, also, that Holy One who is to be born will be called the Son of God [Jesus].’”

•     The trinitarian formula is also found in 1 Peter 1:2, 2 Corinthians 13:14, and 1 Corinthians 12:4–6.


To explain the doctrine of the Trinity, I will take an inductive (scientific) approach. By this I mean I will accumulate general facts in Scripture that lead to a specific conclusion—that the nature of God is triune. The argument will go like this:

1. The Bible teaches that God is one (monotheism) and that He possesses certain attributes that only God can have.

2. Yet when we study the attributes of the Father, the Son, and the Holy Spirit, we discover that all three possess the identical attributes of deity.

3. Thus we can conclude that there is one God eternally existing as three distinct persons.

God Is One (Monotheism)

The Hebrew Shema of the Old Testament is “Hear, O Israel: The Lord our God, the Lord is one!” (Deut. 6:4; see Isa. 43:10; 44:6; 46:9). Some people have argued that this passage actually refutes the concept of the triune nature of God because it states that God is one. But the Hebrew word for “one” in this text is echod, which carries the meaning of unity in plurality. It is the same word used to describe Adam and Eve becoming “one flesh” (Gen. 2:24). Scripture is not affirming that Adam and Eve literally become one person upon marriage. Rather, they are distinct persons who unite in a permanent relationship.

The New Testament confirms the teaching of the Old: “You believe that God is one. You do well; the demons also believe, and shudder” (James 2:19, nasv; see 1 Tim. 2:5; 1 Cor. 8:4; Eph. 4:4–6).

God Has a Certain Nature

Both the Old and New Testaments list the attributes of God. We won’t consider all of them here, but what follows are some of the clearest expressions of what constitutes deity.

•     God is omnipresent (present everywhere at once): Psalm 139:7–10; Jeremiah 23:23–24.

•     God is omniscient (possesses infinite knowledge): Psalms 139:1–4; 147:4–5; Hebrews 4:13; 1 John 3:20.

•     God is omnipotent (all-powerful): Psalm 139:13–18; Jeremiah 32:17; Matthew 19:26.

The Father Is God

To the Jews, who do not accept the Trinity, God is Yahweh. In the Old Testament, Yahweh is to the Hebrews what Father is in the New Testament and to Christians. The attributes of God (Yahweh) listed above are the same for Yahweh and Father because both names apply to the one God. Although the concept of God as Father is not as explicit in the Old Testament as it is in the New, nevertheless, it has its roots in the Old (see Pss. 89:26; 68:5; 103:13; Prov. 3:12).

In the New Testament, the concept of the Father as a distinct person in the Godhead becomes clear (Mark 14:36; 1 Cor. 8:6; Gal. 1:1; Phil. 2:11; 1 Pet. 1:2; 2 Pet. 1:17). God is viewed as Father over creation (Acts 17:24–29), the nation of Israel (Rom. 9:4; see Exod. 4:22), the Lord Jesus Christ (Matt. 3:17), and all who believe in Jesus as Lord and Savior (Gal. 3:26).

The Son Is God

Like the Father, Jesus possesses the attributes of God. He is omnipresent (Matt. 18:20; 28:20). He is also omniscient: He knows people’s thoughts (Matt. 12:25), their secrets (John 4:29), the future (Matt. 24:24–25), indeed all things (John 16:30; 21:17). His omnipotence is also taught. He has all power over creation (John 1:3; Col. 1:16), death (John 5:25–29; 6:39), nature (Mark 4:41; Matt. 21:19), demons (Mark 5:11–15), and diseases (Luke 4:38–41).

In addition to these characteristics, Jesus exhibits other attributes that the Bible acknowledges as belonging only to God. For example, He preexisted with the Father from all eternity (John 1:1–2), accepted worship (Matt. 14:33), forgave sins (Matt. 9:2), and was sinless (John 8:46).

The Holy Spirit Is God

The Holy Spirit is also omnipresent (Ps. 139:7–10), omniscient (1 Cor. 2:10), and omnipotent (Luke 1:35; Job 33:4).

Like Jesus, the Holy Spirit exhibits other divine attributes that the Bible ascribes to God. For instance, He was involved in creation (Gen. 1:2; Ps. 104:30), inspired the authorship of the Bible (2 Pet. 1:21), raised people from the dead (Rom. 8:11), and is called God (Acts 5:3–4).

The upshot of all this is that God is triune. In a formal argument, we can put it this way:

Major Premise:

Only God is omnipresent, omniscient, and omnipotent.

Minor Premise:

The Father, the Son, and the Holy Spirit are omnipresent, omniscient, and omnipotent.


Therefore, God is triune as Father, Son, and Holy Spirit.




In the Bible, Jesus claims to be God and then demonstrates this claim by displaying the attributes of God and by raising Himself from the dead. So what Jesus has to say about God must be true. And Jesus clearly teaches that God is triune.

Jesus Is Equal with the Father and Holy Spirit

In Matthew 28:19, Jesus tells His followers to “make disciples of all the nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit.” He uses the singular word name but associates it with three persons. The implication is that the one God is eternally three co-equal persons—Father, Son, and Holy Spirit.

Jesus Is One with the Father

In John 14:7 and 9, Jesus identifies Himself with the Father by saying to His disciples, “If you had known Me, you would have known My Father also; and from now on you know Him and have seen Him … He who has seen Me has seen the Father” (see John 5:18). Jesus is not claiming to be the Father; rather, He is saying that He is one with the Father in essence.

Jesus Is One with the Holy Spirit

Continuing in John 14, Jesus tells His disciples that, after He is gone, He will send them “another Helper” who will be with them forever and will indwell them (vv. 16–17). The “Helper” is the Holy Spirit. The trinitarian implication lies with the word another. The apostle John, as he wrote this passage, could have chosen one of two Greek words for another. Heteros denotes “another of a different kind,” while allos denotes “another of the same kind as myself.” The word chosen by John was allos, clearly linking Jesus in substance with the Holy Spirit, just as He is linked in substance with the Father in verses 7 and 9. In other words, the coming Holy Spirit will be a different person than Jesus, but He will be the same with Him in divine essence just as Jesus and the Father are different persons but one in their essential nature. Thus, in this passage, Jesus teaches the doctrine of the Trinity.

So far we have seen that the authors of Scripture and Jesus Christ teach the triune nature of God. Therefore, the only way the doctrine of the Trinity can be rejected is if one refuses to accept the biblical evidence. Some groups, such as the Jehovah’s Witnesses, do this by reinterpreting and altering Scripture. Others, such as the Unitarians (who claim that Jesus is just a man), arbitrarily and without any evidence deny anything supernatural or miraculous in the Bible. Both the Jehovah’s Witnesses and the Unitarians are guilty of the very same thing of which they accuse Christians—irrationality. They refuse to accept the evidence for the Trinity regardless of how legitimate it is. This is unscientific and irrational. If one approaches Scripture without bias, he will clearly discover what the church has maintained for centuries: God is triune—one God in essence but eternally existing in three persons as Father, Son, and Holy Spirit.


Perhaps you’ve wondered or heard someone say, “If Jesus is one in essence with the Father, an equal member of the triune Godhead, why does He say, ‘the Father is greater than I’” (John 14:28)? This question actually moves away from the doctrine of the Trinity and launches us into the doctrine of the incarnation, the process whereby Jesus, as the eternal Son of God, came to earth as man. Nevertheless, because this question is frequently raised as an objection, it needs to be answered.

Numerous passages in Scripture teach that Jesus, although fully God, is also fully man (John 1:14; Rom. 8:3; Col. 2:9; 1 Tim. 3:16). However, Philippians 2:5–8 states that, in the process of taking on humanity, Jesus did not give up any of His divine attributes. Rather, He gave up His divine glory (see John 17:5) and voluntarily chose to withhold or restrain the full use of His divine attributes. There are numerous instances in Scripture where Jesus, although in human form, exhibits the attributes of deity. If Jesus had surrendered any of His divine attributes when He came to earth, He would not have been fully God and thus could not have revealed the Father as He claimed to do (John 14:7, 9).

The key to understanding passages such as John 14:28 is that Jesus, like the Father and the Holy Spirit, has a particular position in the triune Godhead. Jesus is called the Son of God, not as an expression of physical birth, but as an expression of His position in relationship to the Father and Holy Spirit. This in no way distracts from His equality with the Father and the Holy Spirit or with His membership in the Godhead. As man, Jesus submits to the Father and acts in accordance to the Father’s will (see John 5:19, 30; 6:38; 8:28). So when we read passages such as Mark 14:36 where Jesus submits to the Father’s will, His submission has nothing to do with His divine essence, power, or authority, only with His position as the Incarnate Son.

Perhaps an illustration will help to explain this. Three people decide to pool their money equally and start a corporation. Each are equal owners of the corporation, but one owner becomes president, another vice-president, and the third secretary/treasurer. Each are completely equal so far as ownership, yet each has his own particular function to perform within the corporation. The president is the corporate head, and the vice-president and secretary/treasurer are submissive to his authority and carry out his bidding.

So when Jesus the God-man submits to the Father’s will or states that the Father is greater than He or that certain facts are known only by the Father (e.g., Matt. 24:36), it does not mean that He is less than the other members of the Godhead but that in His incarnate state He did and knew only that which was according to the Father’s will. The Father did not will that Jesus have certain knowledge while in human form. Because Jesus voluntarily restrained the full use of His divine attributes, He was submissive to the Father’s will.

Why did Jesus choose to hold back from fully using His divine powers? For our sake. God willed that Jesus feel the full weight of man’s sin and its consequences. Because Jesus was fully man, He could fulfill the requirements of an acceptable sacrifice for our sins. Only a man could die for the sins of mankind. Only a sinless man could be an acceptable sacrifice to God. And it is only because Jesus is an equal member of the triune Godhead, and thus fully God, that He was able to raise Himself from the dead after dying on the cross and thereby guarantee our eternal life.

When all the evidence is accounted for and the verdict read, the Bible clearly teaches that the Father, the Son, and the Holy Spirit are three distinct, co-equal, co-eternal members of the Godhead, yet one in essence, power, and authority. All three are one God. Were this not the case, if the Trinity were not a reality, there would be no Christianity.




[1]Story, D. (1997). Defending your faith. Originally published: Nashville : T. Nelson, c1992. (99). Grand Rapids, MI: Kregel Publications.