How in the world do you trace back the myth of God? I don't get it.
You trace back the idea of God (I won't call it a 'myth' for argument's sake) the same way you trace back any human idea: you see how it is transmitted and altered through history.
An example from
an article at UCLA:
AMMAN: In a remote corner of Jordan, archaeologists have uncovered a room that may transform the way we think about God.
Its massive stones still clinging to the damp hills of the Jordan River Valley, the Migdol Temple at first appears to be little more than an ancient network of fortified walls. Yet when Jordanian and Australian archaeologists working at the site of ancient Pella began piecing it together in 1997, it didn't take them long to realize that they were reconstructing something extraordinary: a 3,600-year-old textbook in stone.
The Migdol Temple charts within a single room one of the most important events in human history: the transition from polytheism to the belief in one God.
....
Continuously in use from 1650 BC to 850 BC , the Migdol Temple holds within it hundreds of religious artifacts that point to five very distinct phases of occupation and rebuilding.
Constructed, destroyed, and reconstructed time and time again, the Migdol Temple records changing cult practices during the Canaanite Hyksos ascendancy, then again during the Egyptian New Kingdom Empire, the Philistine Era, and the Age of the Local Kingdoms.
A stone spectator to a period of intense religious and political upheaval, every single one of the periods bruised, scarred, and left its mark on the temple, transforming the unassuming circular stones into a time capsule that is transforming the understanding of religious history.
.....
The newest finds at the Migdol Temple suggest that the region had its own distinct form of monotheism, and that monotheism arose in several areas of the Middle East at once in order to unify small nation-states.
From wiki:
Origin and Development of Monotheism:
The concept sees a gradual development out of notions of
henotheism and
monolatrism. In the
Ancient Near East, each
city had a local patron deity, such as
Shamash at
Larsa or
Sin at
Ur. The first claims of global supremacy of a specific god date to the
Late Bronze Age, with
Akhenaten's
Great Hymn to the Aten (connected to
Judaism by
Sigmund Freud in his
Moses and Monotheism), and, depending on dating issues,
Zoroaster's
Gathas to
Ahura Mazda. Currents of monism or monotheism emerge in
Vedic India in the same period, with e.g. the
Nasadiya Sukta. Philosophical monotheism and the associated concept of absolute
good and evil emerges in
Classical Antiquity, notably with
Plato (c.f.
Euthyphro dilemma), elaborated into the idea of
The One in
Neoplatonism.