The unity of G-d is one of the fundamental principles of Judaism.
The Biblical source for this principle is the first verse of the
Shema (Deut. 6:4). The Moslems too believe that G-d is One (their
profession of faith begins "There is no G-d but G-d..."), and this
belief is also shared by many Christian groups who believe that
Jesus was the Messiah, and was human rather than Divine.
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