Is there evidence of the Trinity in the Old Testament? Truth about God’s nature and personhood has been progressively revealed in Scripture. Therefore, while the Old Testament is clearly limited in what could be considered direct support for the doctrine of the Trinity, the Hebrew Scriptures nevertheless allow for the idea of a plurality of personhood within God’s single nature. This allowance of plurality is evidenced in at least three ways in the Old Testament.
First, while the Hebrew Scriptures strongly present the truth of monotheism (Deuteronomy 6:4; Isaiah 43:10), it is curious and probative that the Hebrew noun for God (‘elohim) is generally found in the plural.
Second, in a handful of Old Testament passages plural pronouns and verbs are used when speaking about God. Three times in the Book of Genesis God speaks of himself in the plural. Genesis 1 records that just as God was about to create man he said, “Let us make man in our image, in our likeness” (Genesis 1:26). The very next verse defines “our image” as being “God’s image.” Similarly, after Adam and Eve’s fall into sin in Genesis 3, God said: “The man has now become like one of us, knowing good and evil” (Genesis 3:22). And following the building of the Tower of Babel, God said: “Come, let us go down and confuse their language” (Genesis 11:7). It is highly unlikely that these mysterious divine plural references can be explained as merely “plurals of majesty.” Nor is it reasonable to conclude that God was speaking to the angels because the comments apply, in context, to the person(s) of God (Genesis 1:26).
Third, in anticipation of the New Testament, references to “Lord,” “Word,” and “Spirit” (or Hebrew: divine breath) are spoken of in the Old Testament within the context of God’s unique activities. For example, Psalms 33:6 says: “By the word of the Lord were the heavens made, their starry host by the breath of his mouth” (emphasis added).
While these Old Testament scriptural passages and others that suggest a divine plurality certainly don’t prove the Trinity, they are consistent with the New Testament apostles’ modification of the traditional understanding of Jewish monotheism. The one true God reveals himself in three distinct persons: Father, Son, and Holy Spirit.
For more on the historic Christian doctrine of the Trinity, see “How Can God Be Three and One?,” in my book Without a Doubt: Answering the 20 Toughest Faith Questions.