When you approach the Hebrew Bible, sans Theological predisposition, it is crystal clear that the "God" presented to the reader is a God who is a Singularity that is also a Plurality.
At the very beginning of the Hebrew Bible, we find God presented as אלהים (Elohim). This is a word that is both singular and plural, like our English word sheep.
For Example:
Singular Usage: In the beginning God (אלהים Elohim) created the heavens and the earth. Gen 1:1
Plural Usage: I said, You are gods (אלהים Elohim), And all of you are sons of the Most High. Psalm 82:6
You then have this God declaring himself "One" in Deut 6:4 using a word for one, (אחד echad), that means "a unity comprised of multiple parts."
Hear, O Israel! The LORD is our God, the LORD is one (אחד Echad)
And then, in Gen 1:26 and in Gen 11:7, this God refers to Himself in the plural:
Then God said, "Let Us make man in Our image, according to Our likeness; and let them rule over the fish of the sea and over the birds of the sky and over the cattle and over all the earth, and over every creeping thing that creeps on the earth." Gen 1:26
Come, let Us go down and there confuse their language, so that they will not understand one another's speech Gen 11:7
Therefore, it certainly comes as no suprise when we go the the Brit HaChadashah, the New Testament and find the Name (singular) of this God is "the Father and the Son and the Holy Spirit" (plural):
Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit Matt 28:19
