We know that God declares that he is one. It is interesting to note however that in Deuteronomy chapter 6 verse 4 where God says, “hear o Israel the Lord your God is one” that the word usage is very important. The word “Lord” is in the Hebrew “Yahweh”. It means the “Creator God” or “the great I am”, the ultimate reality, God Himself. The Lord your God, the word “God” in Hebrew is “Elohim”. It actually is the plural of El which means “Gods”. “The Lord your Gods is but one” is how it would literally read is but one. Hear o Israel, the great “I am” who exists in the plural is but one. The word “one” in Hebrew is “Echad”. The theological word book of the Old Testament has the following information on the word “Echad”. This word occurs 960 times. It is closely identified with “yahad”, which means to be united. It stresses unity while recognizing diversity within that oneness. Likewise it is used in Exodus 24:3 where the people are said to have spoken with “one” voice. In other words, a multiplicity of people yet their voice is one. This expresses the Hebrew word “Echad”. So in this oneness, God declares that he is God Elohim in the plural but that he is one “Echad”. He stresses his unity while recognizing a holy diversity within his oneness.
Christians believe that there is one God but somehow he exists in three persons. Now what’s that all about? Well you know I grew up in a Jewish home and the cardinal tenets of Judaism is the Shema, “hear o Israel the Lord our God the Lord is one,” Yet that’s not a statement that God is mathematically one. It’s a statement of his uniqueness that he alone is the one to be worshipped. And the reason Christians believe God is three-in-one is because that’s where the Bible leads. For example, in the Old Testament we have many suggestions that somehow God is more than one-in-one. The Hebrew “ahad” meaning one is what’s used of God’s oneness. Yet it’s also often used about a compound, a multiple unity. The noun that’s used for God in Hebrew “Elohim” is the plural noun. In Genesis 1:26 God says, “let us make man in our own image.” In 1 Kings 8:27, God fills the universe, yet the Temple in Jerusalem. In Genesis 18 three men visit Abraham and one of them is called “God” and than a “man”, “God” and then a “man” back and forth. In Genesis chapter 32 Jacob wrestles with the angel or with the man all night and when he’s done wrestling he says I’ve seen God face to face and yet I’ve lived. And when we finally come to the New Testament, that’s where things become clearer. Jesus himself used the Old Testament name of God “I am” about himself and Paul the great Jewish monotheists who wrote so much of the New Testament actually calls Jesus God. In the book of Romans God forgives sins. Jesus forgives sins. These things that drove the early Christians to believe that God was three and one. Sure it’s a mystery but the universe is a mystery. Light is a particle and it’s a wave. The universe is finite yet it’s expanding and it’s curved, all mysterious things. Why should the Creator be any less mysterious than his own creation.