No doctrine in scripture is more explicit than the oneness of God. The King James uses these terms: One God (Malachi 2:10; Mark 12:32; Romans 3:30: 1 Corinthians 8:6; Ephesians 4:6; 1 Timothy 2:5; James 2:19). God is one (Galatians 3:20). One Lord (Deuteronomy 6:4; Zechariah 14:9; Mark 12:29; Ephesians 4:5).
Not only does the scripture say that God is one, but further defines this oneness in these terms: alone (Isaiah 44:24), by Himself (Isaiah 44:24), none beside and none else (Isaiah 45:6), above all (2 Chronicles 2:5), none before and none after (Isaiah 43:10).
In addition to this are the thousands of times that singular personal pronouns (He, Him, I, Me) are used of God. While there are a couple references in the English translations to God as “us” they must not be understood in a Trinitarian sense. The Jews, to whom the language belongs, would never have understood God as a pluripersonal being. Some of the “us” passages that are sometimes thought to refer to God, like Isaiah 6:8, clearly do not. The “us” in Isaiah 6:8 does not refer to God alone, but to God and His host (Isaiah 6:3). God is never referred to as “they” or “them.”
“Hear, O Israel: The LORD our God is one LORD:” Deuteronomy 6:4 KJV
Deuteronomy 6:4 is called the Shema, and is the bed rock upon which both the Old and New Testaments are built. The Shema is not only central to Judaism, it is also equally central to Christianity; it is the theology of both covenants. More importantly in the New Testament is the idea that Israel’s God has been revealed in and as Jesus.
As N.T. Wright says:
“…we are to look at Jesus and see in him, however strange it may seem, the personal presence of Israel’s God…”
“…God who, having made humans in his own image, will most naturally express himself in and as that image-bearing creature…”
“…in Jesus, Israel’s God had become present, had become human, had come to live in the midst of his people…”
The idea that Israel’s God had become human in and as Jesus Christ is incredible! That Jesus is the incarnational and personal presence of Israel’s one God is replete throughout the Old Testament (prophetically) and the New Testament (fulfillment).
“Is he the God of the Jews only? is he not also of the Gentiles? Yes, of the Gentiles also:
30 Seeing it is one God, which shall justify the circumcision by faith, and uncircumcision through faith.” Romans 3:29-30 KJV
This verse beautifully illustrates that Israel’s God is the Gentile’s God, and the way that Israel’s God became the Gentile’s God is in the incarnation (2 Corinthians 5:19; 1 Timothy 3:16).
My favorite illustration of Jesus being Israel’s God incarnate is Jeremiah 17:9-10 and Revelation 2:18, 23:
“The heart is deceitful above all things, and desperately wicked: who can know it? 10 I the LORD search the heart, I try the reins, even to give every man according to his ways, and according to the fruit of his doings.”
“These things sayeth the Son of God… all the churches shall know that I am he which searcheth the reins and hearts: and I will give unto every one of you according to your works.” Revelation 2:18, 23
This is a bold claim by the Son of God to be the Old Testament LORD (Yahweh). The New Testament makes two very clear claims: 1. Israel’s God is the only true God. 2. Israel’s one God is revealed in the Person of Christ.
The point of the oneness of God, as I will attempt to demonstrate in this book, is much bigger than creedal confession. The oneness of God is not only the world’s greatest creed, but it is also the world’s great conduct.
 For clarification: I am not quoting N.T. Wright presuming that we share the same Theology or Christology.
 Wright, N. T. (2012-03-13). How God Became King: The Forgotten Story of the Gospels (Kindle Locations 1573-1574). Harper Collins, Inc.. Kindle Edition.
 Wright, N. T. (2012-03-13). How God Became King: The Forgotten Story of the Gospels (Kindle Locations 1706-1709). Harper Collins, Inc.. Kindle Edition.
 Wright, N. T. (2012-03-13). How God Became King: The Forgotten Story of the Gospels (Kindle Locations 1549-1554). Harper Collins, Inc.. Kindle Edition.