The concept and belief that God is one was an essential feature of Old Testament theology. In reviewing a number of passages the primary focus of this book to a large extent has been on Deuteronomy 6:4 (the Shema). Understanding what this meant in ancient Israel provides the clues to a deeper understanding in this present era. A number of materials, studies, documents and references have provided a body of knowledge that will grealy aide and assist any believer to better define, clarify and defend the long held belief, custom and practice that God is one. Other essential factors in this book discuss and to some extent contrast and compare the concept of monotheism and oneness to better explain conceptually how these build the structure and framework that supports the position that God is numerically one.