One of the hardest things to grasp about the nature of God is the idea of the Trinity. It is a stumbling block, especially for my Jewish friends who often ask me, “Doesn’t the Shema clearly say, Hear, O Israel! The LORD is our God, the LORD is ONE (אֶחָד echad)? Then how can God be one and three at the same time?” (see footnote)
I respond with a question of my own: What happens to sunlight when it passes through a prism? They usually know the answer—that we see the spectrum of colors—and say so.
Then I ask: Is the red light still light? They say yes. The orange light? Yes again. And so on through yellow, green, blue, indigo, and violet. As we explore this, it becomes clear that white light can appear to the eye as a unity or, when passed through a prism, as a diversity of colors. Yet whether perceived as one or many, it remains light.
In a similar way—though the comparison has its limits for sure—the Scriptures serve as a kind of prism, through which the God of Israel first revealed Himself to Moses as One (Deuteronomy 6:4), and who, in the fullness of time under the New Covenant, foretold in Jeremiah 31:31-34, has chosen to reveal Himself more fully as Father, Son, and Holy Spirit.
It’s not a perfect analogy. Light is part of the created world, while God is the uncreated Creator. And the picture it paints doesn’t come directly from the Hebrew Scriptures, although the B’rit Hadashah does say metaphorically that “God is light” (1 John 1:5).
With our human limitation, we cannot fully understand the full nature of God’s being. Still, the analogy gives a glimpse—a way to think about how the unity of God and the tri-personal nature of God are not necessarily in conflict. Just as light can be both white and composed of many colors, God can be One and still exist in three persons, without contradiction.
As the B’rit Hadashah puts it: “There are three that bear witness in heaven, the Father, the Word, and the Holy Spirit—and these three are one.” (1 John 5:7)
Footnote
The Hebrew word ‘echad’ (אֶחָד), meaning “one,” is a fascinating term in the Tanakh (Hebrew Bible) because it can indicate both singularity and a unity made up of multiple parts—depending on the context. This dual capacity makes it theologically and linguistically significant.
Basic Meaning: “One” (Singular)
‘Echad’ is often used to refer to a single individual, object, or day. Examples of the singular use include:
Genesis 1:5 – “And there was evening, and there was morning—the first (echad) day.”
Genesis 2:11 – “The name of the first (echad) river is Pishon…” These are clearly instances of numerical singularity.
Compound Unity: “One” Made of Many
However, ‘echad’ can also describe a composite or collective unity—where multiple things or persons are treated as a single unit, Examples of such usage are found in:
Genesis 2:24 – “…and they shall become one (echad) flesh.” Refers to two individuals (man and woman) becoming a unified couple.
Genesis 11:6 – “Behold, they are one (echad) people, and they all have the same language” describes many people as a single unified group.
Exodus 26:6 – “…the tabernacle shall be one (echad).” Refers to many parts (curtains, loops, clasps) being joined into a unified whole.
So ‘echad’ does not demand absolute singularity. It can easily imply a unity of plurality—a collective oneness.
Theological Significance: Deuteronomy 6:4
“Hear, O Israel: the LORD our God, the LORD is one (echad).” (שְׁמַע יִשְׂרָאֵל יְהוָה אֱלֹהֵינוּ יְהוָה אֶחָד) This is one of the most familiar uses of ‘echad’. Some argue this affirms God’s singularity (against polytheism), while others see in it room for a complex unity—a view used by Christians to support the concept of the Trinity, pointing to how ‘echad’ allows for a plurality-within-unity.
Contrast with ‘Yachid’ (יָחִיד)
‘Yachid’ means “only” or “solitary one”, as in Genesis 22:2, “Take your son, your only (yachid) son Isaac…” If the Tanakh intended to stress absolute singularity or indivisibility, ‘yachid’ would be the more precise term. But ‘echad’ is used in the Shema instead—to explain the various ways that man can perceive the nature of God as he progressively reveals himself over time.