Deuteronomy 6:4 declares,  “Hear, O Israel: The LORD our God, the LORD is one!”  So, why do Christians believe that God is three persons: the Father, the Son, and the Holy Spirit?  And, why do Christians claim that they worship only one God, despite the fact that they believe that God is triune (i.e., a trinity comprised of three “Persons”).  As a result of this seeming incongruity, many non-Christians think Christians worship three gods rather than only one.

On page 107 of the winter 2019-2020 edition of the Explore the Bible: Leader Guide, a publication which is used by many churches in Bible studies, Deuteronomy 6:4 is explained as follows:

[I]n Hebrew as in English, the word one does not describe singleness of purpose.  The Lord is one is not the same as “the Lord has one purpose.”  When the Bible intends to speak of God’s unchanging singleness of purpose, it uses an expression like Malachi 3:6, “I, the Lord, have not changed. . . .”  The idea is true – God is consistent in all He does – but Deuteronomy 6:4 does not express that idea.

The following translation [of Deuteronomy 6:4] is possible: “Listen, Israel: Yahweh is our God!  Yahweh is our one God!”  The verse does not assert a unitarian view of God, nor is it a claim about monotheism, nor does it claim that Yahweh is unique or single in purpose.  It is a claim that, unlike the pagans, Israel has only one deity.  It demands that the Israelites show complete faithfulness to Yahweh alone and not worship any other.  Fidelity to Yahweh, Israel’s one God, is the point of the verse.

Unger’s Bible Dictionary explains the concept of the Trinity as follows:

[The Trinity is] the term by which is expressed the unity of three persons in the one God.  The Christian doctrine is: 1. That there is only one God, one divine nature and being.  2. This one divine being is tripersonal [sic], involving the distinctions of the Father, the Son, and the Holy Spirit.  3. These three are joint partakers of the same nature and majesty of God.

Unger goes on to make the following acknowledgment:

It is admitted by all who thoughtfully deal with this subject that the Scripture revelation here leads us into the presence of a deep mystery; and that all human attempts at expression are of necessity imperfect.  The word person, it may be, is inadequate, and is doubtless used often in a way that is misleading.

Neither of the two following illustrations adequately explains the phenomenon of the trinity of God, but they each may provide some insight as to how God can reveal Himself in the forms of three different Persons.

It is said that Saint Patrick, when he first began to teach the people of Ireland about Christianity, used the shamrock as an example to explain the concept of the Trinity.  He used the shamrock, which is a plant like a clover, because it has three distinct leaves that are united on one stalk.  Likewise, God is three “Persons,” Who together reveal different aspects as to Who He is.

Water provides another illustration of how it is possible for God to reveal Himself in the forms of three Persons, yet be only one God.  When water is in what probably is its most common form, it is liquid.  But, if water is heated to a sufficiently high temperature, it becomes vapor or steam.  However, if water is cooled to a low enough temperature, it will freeze and take the form of ice.

First, we will consider what the Old Testament indicates regarding whether or not God is a plural Being.  [Note:  When we quote Scripture in this article, we use the wording in the New King James Version of the Bible, unless we indicate otherwise.]

In Genesis 1:26, God says, “Let Us make man in Our image, according to Our likeness    . . . .”  The plural pronouns that are used in this verse of scripture appear to support the concept that God is a plural Being.  And, prior verses in the first chapter of Genesis also support this concept.

In this regard, John MacArthur, President of The Master’s College and Seminary, asserts on page 160 of his book entitled The Battle for the Beginning,

The fact of multiple Persons in the Godhead has been hinted at in the Hebrew word for God that is used in twenty-one of the first twenty-five verses of Scripture, because elohim takes the form of a plural noun in Hebrew.  But the plural pronouns of verse 26 make the point even more forcefully.  It is by no means a full revelation of the doctrine of the Trinity, but it is an unmistakable reference to plurality within the Godhead, and it begins to lay the groundwork for what we later learn of the Trinity from the New Testament.

Marvin J. Rosenthal¸ in “Elohim: The Strong, Faithful One,” an article in the September – October 2020 issue of the publication entitled  Zion’s Fire, amplifies what MacArthur says regarding the Hebrew word elohim.  On page 17 of this publication,  Rosenthal explains,

The Hebrew word translated “one” is sometimes used as a uni-plural noun.  That is, it sometimes means a “oneness” in plurality.  For example: God said of Adam and Eve, “They [two] shall be one [echad] flesh (Genesis 2:24).  Adam and Eve were each a total entity.  They both possessed intellect, emotion, and will – they could think, feel, and act.  They existed independently of each other.  Yet, when they united as husband and wife, though two distinct beings, they so complemented one another that in an ultimate sense they were one (echad).

Within the unity [oneness] of the Godhead there are three persons: As Adam and Eve were on (echad), so too – within the Godhead – Father, Son, and Holy Spirit are one (echad) – not three gods in one person, but one God in three persons – a mystery of oneness.

Subsequently, on page 19 of the same publication, Rosenthal asserts,

Jewish scholars have long understood that Elohim is a plural word.  They also understood that this leaves room for the Christian doctrine of the Trinity.  Since they could not deny the plurality of this name, they suggested that Elohim is used as a plural of “majesty”; that the plural is used simply to pay homage to kingship.  To my knowledge, there is neither biblical nor historical precedent to warrant such a view in the Hebrew language.

Another scripture to consider is Isaiah 48:16, which states, “Come near to Me, hear this: I have not spoken in secret from the beginning; from the time that it was, I was there.  And now the Lord God and His Spirit have sent Me.”  Note that “the Lord God” and “His Spirit” are referred to as two distinct Persons.   And, the narrator who was sent by the Lord God and His Spirit is the Son of God, as indicated by verse 12, which includes the statement by the narrator that “I am the First, I am also the Last.” Thus, Isaiah 48:16 provides a basis for the concept of the Trinity (i.e., that God is three Persons).

Now, we will consider what the New Testament indicates about whether or not God is a plural Being.  John 1: 1-2 and 14-15 provides perhaps the strongest support in the New Testament for the doctrine of the Trinity.  These verses of scripture declare,

In the beginning was the Word, and the Word was with God, and the Word was God.  He was in the beginning with God.

And the Word became 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 [the Baptist] bore witness of Him. . . .

These verses in the Book of John make it sufficiently clear that Jesus Christ is “the Word” and that He was the One of whom John the Baptist bore witness.

However, some people assert that John 1:1 should say that “the Word was a god,” rather than that “the Word was God.”  (Note:  Webster’s Dictionary defines a god as “a person or thing deified or excessively honored and admired.”)  These people believe that God has revealed Himself in only one form, not in the three forms of the Trinity of God.  As a result, they argue that Jesus Christ is merely “a god,” rather than one of three forms of God.  But, there is no biblical support for believing that God chose to create a separate being to serve as a god to co-exist with Him in heaven.

Furthermore, the Bible indicates that God is jealous when any other god is reverenced instead of Him.  So, it is not logical that He would create such a god.  Therefore, Jesus Christ is not a created god.

First John 5:7 may seem to be another New Testament scripture passage that strongly supports belief in the triune nature of God.  This passage states, “[T]here are three who bear witness in heaven: the Father, the Word, and the Holy Spirit; and these three are one.”

However, The Wycliffe Bible Commentary states with regard to this verse,

The text of this verse should read, Because there are three that bear record. The remainder of the verse is spurious.  Not a single manuscript contains the Trinitarian addition before the fourteenth century, and the verse is never quoted in the controversies over the Trinity in the first 450 years of the church era.

Norman Geisler, Ph.D. and Thomas Howe, M.A., on pages 540-541 of their book entitled When Critics Ask, provide the following additional perspective regarding 1 John 5:7:

This verse has virtually no support among the early Greek manuscripts, though it is found in Latin manuscripts.

Its inclusion in the Latin Bible probably results from a scribe incorporating a marginal comment . . . into the text as he copied the manuscript of 1 John.

Although 1 John 5:7 does not have credibility as a biblical passage that supports the doctrine of The Trinity, the New Testament as a whole does.  Unger’s Bible Dictionary says, “The same worship is paid, the same works are ascribed to each of these three persons [i.e., God the Father, Jesus Christ, and the Holy Spirit], and in such a way as to indicate that these three are united in the fullness of the one living God.”

Conclusion

On the basis of the foregoing considerations, we think it is reasonable to conclude that Christians worship only one God, who manifests Himself in the form of three different Persons.