The rule of Amenhotep III. was calm, peaceful and prospering. The land had never flourished like this before and Thebes (Waset) became an enviable capital. So how could it happen that Amenhotep IV. (Akhenaten) arrived at a decision to change the religious principles so radically?
Causes of religious reform
The first cause could be the mutual enmity between the young king and the priesthood of Amun's temple in Karnak. The young king considered them as too self-confident group of conspirators, because his predecessors showered this priesthood with wealth and privileges. It is just the temple in Karnak that is the symbol of their wealth and influence. Amenhotep IV. decided to end this domination, when he became the Pharaoh. Also Nefertiti, his wife, had a great share in this decision.
The second cause could be the god Aten himself. Aten was the god of Heliopolis, which was situated to the north from today's Cairo. Actually this sun god without face was a solar version of the god Amun and his connection Amun-Ra. The cult of god Aten "became fashionable" already in the Middle Kingdom period and it was discovered later by Amenhotep III – he even gave a ship named "Aten's beauty" to his wife Tiye.
The cult of Aten
The cult of Aten celebrated only the life and freedom and didn't take in the death in contrary to the previous religion. The main principle of its teachings was simplicity. Akhenaten introduced Aten as a solar disc to people which was an understandable symbol for all.
The cult of Aten was worshipped in temples and outdoors as well. Akhenaten and his wife Nefertiti were the main servants of this cult. The ceremony included prayers and hymns celebrating the Sun and they were accompanied with music.
Akhenaten and Nefertiti with children