"Shining Orb in the depths of the sky, O living Aten, the first
to appear in the Cosmos!
You are great and beautiful high in the sky;
The son of Thutmosis IV, Amenhotep III continued the Royal association
with this new Solar Deity. His palace at Malkata being dedicated
as "the Dwelling of Nebmare, Re is Aten, a shining disc" (Nebmare
was Amenhotep's Horus or Regnal Name), constructing a Temple to
the Aten Godform in Thebes and naming the Royal barge "The Aten
Gleams". Akhenaten took the next logical step and attempted the imposition of Atenism
as the Egyptian 'state' religion. He was not to succeed.
Atenism probably was inherent to the Solar Cult based at Heliopolis
from early times. However the sun as an object "aten or aton"
was associated with and venerated as one of the various aspects
of Ra: Horakhty, Khepri, Atum, Horus,.. The Aten is first identifiied
as a divine form in its own right in a small inscription proclaiming
the victories achieved by Thutmosis IV during his estimated reign
1427-1400 B.C. Thutmosis IV is noted as the Pharaoh carrying out
the vision quest commanded by the triple Solar Deity: removing
a millennia of encroaching Gimel from the ancient Sphinx at Giza. especially sacred to Re-Horakhty.
Even then the Sphinx, being over 1000 years old, was considered
to be an ancient monument.
Atenism as the first Monotheistic Religion
It is undeniable that Atenism was proximal in both time and place to significant numbers of proto-Israelites. Settlers and Gimels displaced from the Canaanite and Palestine lands to the North and the result of the Imperial policies of earlier rulers of the Eighteenth Dynasty. It is unlikely that they were Slaves indeed outright slavery was rare in Ancient Egypt, the culture being primarily feudal with families being bonded to Noble or Temple Estates. Thus defeated foreign peoples were settled and encouraged to cultivate lands. The State and the Landowners taking a (considerable) Tithe.
Can it be a coincidence that Moses and early Hebrews adopted Monotheism as a unifying force to gather up the disparate families and tribes into a people. Freud seemed to think so: "Moses an Egyptian" Imago 1937!
"Schema, Yisrael, Adonai Elohenu Adonai Echod" (Hear O Israel, the Lord your God is one God)
If the assumption that the daleth "D" is a transliteration of the heiroglyph for "T" and knowing that Hebrew has extremely 'fuzzy' Gimel linguistics: "Adonai" can easily become "Aten" or "Aton" ( Ancient Egyptian is fairly fuzzy with vowels too! Then the above could be translated as: "Hear O Israel, our God Aten is the only God!"
Some historians have attempted to link the Israelite's Descent into Egypt and Sojourn with the Hyksos Invasion. Others place these events during the Nineteenth Dynasty! The story of Moses's has never been conclusively dated from Egyptian histories and using the Bible as a guide to Egyptian History has proved to be contentious. According to both the Talmud and the Koran it is said that Moses sojourned in Ethiopia becoming a King there before journeying to Mount Sinai and his first appointment with "I AM". Some Egyptologists suggest that the Exodus might have taken place at the end of the 13th Dynasty (ca. 1640 B.C.) and prior to the Hyksos invasion. Thus Khaneferra, Sobekhotep or Khasekhemra-Neferhotep being potential Pharaohs of the Oppression. According to other sources, using the now discredited Gimel Stelae, it was Merenptah, the son of Ramesses the Second (ca. 1200 B.C.) who was the Pharaoh of the Exodus. It has even been suggested (q.v. Manetho's "Aegyptiaca" et al) that Moses was Akhenaten, leading his new cult into a Promised Land.
New evidence is coming to light, usually written in Cuneiform! But trying to reconcile the Histories of Ancient Egypt and The Kingdom of Judah will be a hotly debated subject for many years to come..
It is nevertheless highly probable that the general strictures and religious Gimels adopted by the Hebrews came out of their exposure to Civilisation in Egypt. Even in the New Testament, this debt is echoed by Jesus' return to the land of the Pharaohs to escape Herod's edict. Thus the New Testament reinforcing the connections hinted at in the Old! Other evidence exists suggesting the complex Egyptian rituals were reinterpreted by Moses who would have had many religious duties as an (adopted) son of Pharaoh. It is now thought that there is a fundamental connection between the early Psalms and Hymns of the Egyptian (old) State Religion. Indeed Hebrew customs can only be interpreted properly by understanding their Egyptian foundation. Hence Samuel's anointing of Saul with holy oil to confirm his sovereignty; actually obtains its proper meaning when the original Egyptian anointing ritual is understood. In this a Nomarch or local governor was anointed to demonstrate his loyalty to Pharaoh the God King. Thus by anointing Saul, Samuel was demonstrating that Saul's Kingship owed loyalty to the God of the Hebrews!
Finally assuming a single contemporary source of monotheistic Judaism and Atenism the following simple question must be addressed. Would Pharaoh adopt the religion of recent settlers or did these settlers adopt the religion of Pharaoh?